Phase 1+2 구현: Electron 뼈대 + STT/핫키/오케스트레이터

Phase 1:
- 프로젝트 초기화 (TypeScript strict, electron-vite, ESLint, Prettier)
- shared 타입 (ipc-channels 113채널, types, errors, constants)
- 메인 프로세스 뼈대 (bootstrap, lifecycle, 단일 인스턴스)
- LoggerService, ConfigService (electron-store ESM dynamic import)
- React 19 + MUI 7 Dashboard, 시스템 트레이

Phase 2:
- AudioCaptureService (node-record-lpcm16, PCM16 16kHz mono)
- HotkeyService (uiohook-napi, 더블프레스, holdMode/toggleMode)
- LocalSTTService (faster-whisper Python sidecar, 이중 조건 플러시)
- VoiceModeService 오케스트레이터 (이중 상태머신, Action Queue)
- Python sidecar (FastAPI: health/load/transcribe/shutdown)
- IPC 핸들러 (voice, stt, hotkey) + Preload API 확장

src/main/bootstrap.ts

@@ -0,0 +1,78 @@
+// src/main/bootstrap.ts — 초기화 시퀀스
+
+import { app, dialog } from 'electron'
+import { initLoggerService, getLogger } from './services/LoggerService'
+import { initConfigService } from './services/ConfigService'
+import { getHotkeyService } from './services/HotkeyService'
+import { getVoiceModeService } from './services/VoiceModeService'
+import { createMainWindow } from './windows/WindowManager'
+import { createTray } from './windows/TrayManager'
+import { registerAllIpcHandlers } from './ipc'
+
+const logger = getLogger('bootstrap')
+
+interface BootstrapStep {
+  name: string
+  critical: boolean
+  fn: () => Promise<void>
+}
+
+export async function bootstrap(): Promise<void> {
+  const steps: BootstrapStep[] = [
+    { name: 'logger', critical: false, fn: initLogger },
+    { name: 'config', critical: false, fn: initConfig },
+    { name: 'create-windows', critical: true, fn: createWindows },
+    { name: 'tray', critical: false, fn: initTray },
+    { name: 'ipc-handlers', critical: true, fn: initIpcHandlers },
+    { name: 'hotkey', critical: false, fn: initHotkey },
+    { name: 'voice-mode', critical: false, fn: initVoiceMode }
+  ]
+
+  for (const step of steps) {
+    try {
+      await step.fn()
+      logger.info(`[bootstrap] ${step.name} initialized`)
+    } catch (error) {
+      logger.error(`[bootstrap] ${step.name} failed:`, error)
+      if (step.critical) {
+        dialog.showErrorBox(
+          'D3RO-VOICE 초기화 실패',
+          `${step.name}: ${error instanceof Error ? error.message : String(error)}`
+        )
+        app.quit()
+        return
+      }
+    }
+  }
+}
+
+async function initLogger(): Promise<void> {
+  initLoggerService()
+}
+
+async function initConfig(): Promise<void> {
+  initConfigService()
+}
+
+async function createWindows(): Promise<void> {
+  createMainWindow()
+}
+
+async function initTray(): Promise<void> {
+  createTray()
+}
+
+async function initIpcHandlers(): Promise<void> {
+  registerAllIpcHandlers()
+}
+
+async function initHotkey(): Promise<void> {
+  const hotkey = getHotkeyService()
+  hotkey.loadFromConfig()
+  hotkey.start()
+}
+
+async function initVoiceMode(): Promise<void> {
+  const voiceMode = getVoiceModeService()
+  voiceMode.connectHotkey()
+}

src/main/index.ts

@@ -0,0 +1,34 @@
+// src/main/index.ts — 앱 진입점
+
+import { app } from 'electron'
+import { bootstrap } from './bootstrap'
+import { setupLifecycle } from './lifecycle'
+import { getMainWindow } from './windows/WindowManager'
+
+// 단일 인스턴스 잠금
+const gotTheLock = app.requestSingleInstanceLock()
+
+if (!gotTheLock) {
+  app.quit()
+} else {
+  app.on('second-instance', () => {
+    // 기존 인스턴스의 메인 윈도우를 활성화
+    const mainWindow = getMainWindow()
+    if (mainWindow) {
+      if (mainWindow.isMinimized()) mainWindow.restore()
+      mainWindow.focus()
+    }
+  })
+
+  app.whenReady().then(async () => {
+    await bootstrap()
+    setupLifecycle()
+  })
+
+  app.on('window-all-closed', () => {
+    // Windows에서는 모든 윈도우 닫아도 앱 유지 (트레이)
+    if (process.platform !== 'darwin') {
+      // closeToTray 설정 확인은 lifecycle에서 처리
+    }
+  })
+}

src/main/ipc/audio-handlers.ts

@@ -0,0 +1,37 @@
+// src/main/ipc/audio-handlers.ts
+
+import { ipcMain } from 'electron'
+import { IPC_CHANNELS } from '@shared/ipc-channels'
+import { ipcSuccess, ipcError, ErrorCode } from '@shared/errors'
+import { getAudioCaptureService } from '../services/AudioCaptureService'
+import { configGet, configSet } from '../services/ConfigService'
+import type { SetDeviceParams } from '@shared/types'
+
+export function registerAudioHandlers(): void {
+  ipcMain.handle(IPC_CHANNELS.AUDIO.GET_DEVICES, async () => {
+    try {
+      const devices = await getAudioCaptureService().getDevices()
+      return ipcSuccess(devices)
+    } catch {
+      return ipcError(ErrorCode.AudioDeviceNotFound, 'Failed to enumerate audio devices')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.AUDIO.GET_SELECTED_DEVICE, async () => {
+    return ipcSuccess(configGet('selectedDeviceId'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.AUDIO.SET_SELECTED_DEVICE, async (_event, params: SetDeviceParams) => {
+    try {
+      configSet('selectedDeviceId', params.deviceId)
+      return ipcSuccess(undefined)
+    } catch {
+      return ipcError(ErrorCode.AudioDeviceNotFound, 'Failed to set device')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.AUDIO.TEST_DEVICE, async () => {
+    // Phase 1: 스텁
+    return ipcSuccess({ averageLevel: 0, peakLevel: 0, hasAudio: false })
+  })
+}

src/main/ipc/config-handlers.ts

@@ -0,0 +1,72 @@
+// src/main/ipc/config-handlers.ts
+
+import { ipcMain } from 'electron'
+import { IPC_CHANNELS } from '@shared/ipc-channels'
+import { ipcSuccess, ipcError, ErrorCode } from '@shared/errors'
+import { configGet, configSet, configGetAll, configReset } from '../services/ConfigService'
+import type {
+  ConfigGetParams,
+  ConfigSetParams,
+  ConfigResetParams,
+  SetThemeParams,
+  SetLanguageParams,
+  AppConfig
+} from '@shared/types'
+
+export function registerConfigHandlers(): void {
+  ipcMain.handle(IPC_CHANNELS.CONFIG.GET, async (_event, params: ConfigGetParams) => {
+    try {
+      return ipcSuccess(configGet(params.key))
+    } catch {
+      return ipcError(ErrorCode.ConfigReadFailed, `Failed to read config key: ${params.key}`)
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.SET, async (_event, params: ConfigSetParams) => {
+    try {
+      configSet(params.key, params.value as AppConfig[typeof params.key])
+      return ipcSuccess(undefined)
+    } catch {
+      return ipcError(ErrorCode.ConfigWriteFailed, `Failed to write config key: ${params.key}`)
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.GET_ALL, async () => {
+    return ipcSuccess(configGetAll())
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.RESET, async (_event, params: ConfigResetParams) => {
+    try {
+      configReset(params.key)
+      return ipcSuccess(undefined)
+    } catch {
+      return ipcError(ErrorCode.ConfigResetFailed, 'Failed to reset config')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.GET_THEME, async () => {
+    return ipcSuccess(configGet('theme'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.SET_THEME, async (_event, params: SetThemeParams) => {
+    configSet('theme', params.theme)
+    return ipcSuccess(undefined)
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.GET_LANGUAGE, async () => {
+    return ipcSuccess(configGet('language'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.SET_LANGUAGE, async (_event, params: SetLanguageParams) => {
+    configSet('language', params.language)
+    return ipcSuccess(undefined)
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.GET_AUTO_LAUNCH, async () => {
+    return ipcSuccess(configGet('autoLaunch'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.CONFIG.GET_CLOSE_TO_TRAY, async () => {
+    return ipcSuccess(configGet('closeToTray'))
+  })
+}

src/main/ipc/hotkey-handlers.ts

@@ -0,0 +1,67 @@
+// src/main/ipc/hotkey-handlers.ts
+
+import { ipcMain } from 'electron'
+import { IPC_CHANNELS } from '@shared/ipc-channels'
+import { ipcSuccess, ipcError, ErrorCode } from '@shared/errors'
+import { getHotkeyService } from '../services/HotkeyService'
+import { configGet, configSet } from '../services/ConfigService'
+import type { SetHotkeyParams, SetEnabledParams } from '@shared/types'
+
+export function registerHotkeyHandlers(): void {
+  ipcMain.handle(IPC_CHANNELS.HOTKEY.GET_DICTATION_SHORTCUT, async () => {
+    return ipcSuccess(configGet('dictationShortcut'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.HOTKEY.SET_DICTATION_SHORTCUT, async (_event, params: SetHotkeyParams) => {
+    try {
+      configSet('dictationShortcut', params.binding)
+      getHotkeyService().loadFromConfig()
+      return ipcSuccess(undefined)
+    } catch {
+      return ipcError(ErrorCode.HotkeyRegistrationFailed, 'Failed to set dictation shortcut')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.HOTKEY.GET_HANDS_FREE_SHORTCUT, async () => {
+    return ipcSuccess(configGet('handsFreeShortcut'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.HOTKEY.SET_HANDS_FREE_SHORTCUT, async (_event, params: SetHotkeyParams) => {
+    try {
+      configSet('handsFreeShortcut', params.binding)
+      getHotkeyService().loadFromConfig()
+      return ipcSuccess(undefined)
+    } catch {
+      return ipcError(ErrorCode.HotkeyRegistrationFailed, 'Failed to set hands-free shortcut')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.HOTKEY.GET_COMMAND_SHORTCUT, async () => {
+    return ipcSuccess(configGet('commandShortcut'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.HOTKEY.SET_COMMAND_SHORTCUT, async (_event, params: SetHotkeyParams) => {
+    try {
+      configSet('commandShortcut', params.binding)
+      getHotkeyService().loadFromConfig()
+      return ipcSuccess(undefined)
+    } catch {
+      return ipcError(ErrorCode.HotkeyRegistrationFailed, 'Failed to set command shortcut')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.HOTKEY.IS_ENABLED, async () => {
+    return ipcSuccess(configGet('hotkeyEnabled'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.HOTKEY.SET_ENABLED, async (_event, params: SetEnabledParams) => {
+    configSet('hotkeyEnabled', params.enabled)
+    const hotkey = getHotkeyService()
+    if (params.enabled) {
+      hotkey.start()
+    } else {
+      hotkey.stop()
+    }
+    return ipcSuccess(undefined)
+  })
+}

src/main/ipc/index.ts

@@ -0,0 +1,23 @@
+// src/main/ipc/index.ts — IPC 핸들러 일괄 등록
+
+import { registerAudioHandlers } from './audio-handlers'
+import { registerConfigHandlers } from './config-handlers'
+import { registerWindowHandlers } from './window-handlers'
+import { registerSystemHandlers } from './system-handlers'
+import { registerVoiceHandlers } from './voice-handlers'
+import { registerSTTHandlers } from './stt-handlers'
+import { registerHotkeyHandlers } from './hotkey-handlers'
+import { getLogger } from '../services/LoggerService'
+
+const logger = getLogger('ipc')
+
+export function registerAllIpcHandlers(): void {
+  registerAudioHandlers()
+  registerConfigHandlers()
+  registerWindowHandlers()
+  registerSystemHandlers()
+  registerVoiceHandlers()
+  registerSTTHandlers()
+  registerHotkeyHandlers()
+  logger.info('All IPC handlers registered')
+}

src/main/ipc/stt-handlers.ts

@@ -0,0 +1,52 @@
+// src/main/ipc/stt-handlers.ts
+
+import { ipcMain } from 'electron'
+import { IPC_CHANNELS } from '@shared/ipc-channels'
+import { ipcSuccess, ipcError, ErrorCode } from '@shared/errors'
+import { getLocalSTTService } from '../services/LocalSTTService'
+import { configGet, configSet } from '../services/ConfigService'
+import type { SetSTTModelParams, SetSTTLanguageParams } from '@shared/types'
+
+export function registerSTTHandlers(): void {
+  ipcMain.handle(IPC_CHANNELS.STT.GET_STATUS, async () => {
+    try {
+      const stt = getLocalSTTService()
+      return ipcSuccess(stt.getStatus())
+    } catch {
+      return ipcError(ErrorCode.STTSidecarCommunicationFailed, 'Failed to get STT status')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.STT.GET_MODELS, async () => {
+    try {
+      const stt = getLocalSTTService()
+      return ipcSuccess(await stt.getModels())
+    } catch {
+      return ipcError(ErrorCode.STTModelNotFound, 'Failed to get models')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.STT.GET_ACTIVE_MODEL, async () => {
+    return ipcSuccess(configGet('sttModelId'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.STT.SET_MODEL, async (_event, params: SetSTTModelParams) => {
+    try {
+      configSet('sttModelId', params.modelId)
+      const stt = getLocalSTTService()
+      await stt.initialize(params.modelId)
+      return ipcSuccess(undefined)
+    } catch {
+      return ipcError(ErrorCode.STTModelLoadFailed, 'Failed to set STT model')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.STT.GET_LANGUAGE, async () => {
+    return ipcSuccess(configGet('sttLanguage'))
+  })
+
+  ipcMain.handle(IPC_CHANNELS.STT.SET_LANGUAGE, async (_event, params: SetSTTLanguageParams) => {
+    configSet('sttLanguage', params.language)
+    return ipcSuccess(undefined)
+  })
+}

src/main/ipc/system-handlers.ts

@@ -0,0 +1,28 @@
+// src/main/ipc/system-handlers.ts
+
+import { ipcMain, app, systemPreferences } from 'electron'
+import { IPC_CHANNELS } from '@shared/ipc-channels'
+import { ipcSuccess } from '@shared/errors'
+import type { PermissionStatus } from '@shared/types'
+
+export function registerSystemHandlers(): void {
+  ipcMain.handle(IPC_CHANNELS.SYSTEM.GET_PLATFORM, async () => {
+    return ipcSuccess(process.platform)
+  })
+
+  ipcMain.handle(IPC_CHANNELS.SYSTEM.GET_VERSION, async () => {
+    return ipcSuccess(app.getVersion())
+  })
+
+  ipcMain.handle(IPC_CHANNELS.SYSTEM.CHECK_MIC_PERMISSION, async () => {
+    let status: PermissionStatus = 'unknown'
+    if (process.platform === 'darwin') {
+      const macStatus = systemPreferences.getMediaAccessStatus('microphone')
+      status = macStatus === 'granted' ? 'granted' : macStatus === 'denied' ? 'denied' : 'unknown'
+    } else {
+      // Windows: 마이크 권한은 별도 체크 불필요 (시스템 설정에서 관리)
+      status = 'granted'
+    }
+    return ipcSuccess(status)
+  })
+}

src/main/ipc/voice-handlers.ts

@@ -0,0 +1,53 @@
+// src/main/ipc/voice-handlers.ts
+
+import { ipcMain } from 'electron'
+import { IPC_CHANNELS } from '@shared/ipc-channels'
+import { ipcSuccess, ipcError, ErrorCode } from '@shared/errors'
+import { getVoiceModeService } from '../services/VoiceModeService'
+import type { StartRecordingParams, StopRecordingParams, CancelRecordingParams, SetVoiceModeParams } from '@shared/types'
+
+export function registerVoiceHandlers(): void {
+  ipcMain.handle(IPC_CHANNELS.VOICE.START_RECORDING, async (_event, params: StartRecordingParams) => {
+    try {
+      const voice = getVoiceModeService()
+      await voice.startSession('dictation')
+      const session = voice.currentSession
+      return ipcSuccess({ sessionId: session?.id ?? params.sessionId ?? '' })
+    } catch {
+      return ipcError(ErrorCode.AudioCaptureStartFailed, 'Failed to start recording')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.VOICE.STOP_RECORDING, async (_event, params: StopRecordingParams) => {
+    try {
+      const voice = getVoiceModeService()
+      await voice.stopSession()
+      return ipcSuccess({
+        sessionId: params.sessionId,
+        text: voice.currentSession?.transcription ?? '',
+        durationMs: voice.currentSession ? Date.now() - voice.currentSession.startedAt : 0
+      })
+    } catch {
+      return ipcError(ErrorCode.STTTranscriptionFailed, 'Failed to stop recording')
+    }
+  })
+
+  ipcMain.handle(IPC_CHANNELS.VOICE.CANCEL_RECORDING, async (_event, _params: CancelRecordingParams) => {
+    getVoiceModeService().cancelSession()
+    return ipcSuccess(undefined)
+  })
+
+  ipcMain.handle(IPC_CHANNELS.VOICE.GET_STATE, async () => {
+    return ipcSuccess(getVoiceModeService().getState())
+  })
+
+  ipcMain.handle(IPC_CHANNELS.VOICE.SET_MODE, async (_event, params: SetVoiceModeParams) => {
+    // Phase 2: 모드만 설정에 저장 (실제 모드 전환은 핫키에서 처리)
+    return ipcSuccess(undefined)
+  })
+
+  ipcMain.handle(IPC_CHANNELS.VOICE.GET_MODE, async () => {
+    const voice = getVoiceModeService()
+    return ipcSuccess(voice.currentSession?.mode ?? 'dictation')
+  })
+}

src/main/ipc/window-handlers.ts

@@ -0,0 +1,31 @@
+// src/main/ipc/window-handlers.ts
+
+import { ipcMain } from 'electron'
+import { IPC_CHANNELS } from '@shared/ipc-channels'
+import { ipcSuccess } from '@shared/errors'
+import { getMainWindow } from '../windows/WindowManager'
+
+export function registerWindowHandlers(): void {
+  ipcMain.on(IPC_CHANNELS.WINDOW.MINIMIZE, () => {
+    getMainWindow()?.minimize()
+  })
+
+  ipcMain.on(IPC_CHANNELS.WINDOW.MAXIMIZE, () => {
+    const win = getMainWindow()
+    if (win) {
+      if (win.isMaximized()) {
+        win.unmaximize()
+      } else {
+        win.maximize()
+      }
+    }
+  })
+
+  ipcMain.on(IPC_CHANNELS.WINDOW.CLOSE, () => {
+    getMainWindow()?.close()
+  })
+
+  ipcMain.handle(IPC_CHANNELS.WINDOW.IS_MAXIMIZED, async () => {
+    return ipcSuccess(getMainWindow()?.isMaximized() ?? false)
+  })
+}

src/main/lifecycle.ts

@@ -0,0 +1,37 @@
+// src/main/lifecycle.ts — 종료 시퀀스
+
+import { app } from 'electron'
+import { getLogger } from './services/LoggerService'
+import { getConfigService } from './services/ConfigService'
+
+const logger = getLogger('lifecycle')
+
+let isQuitting = false
+
+export function getIsQuitting(): boolean {
+  return isQuitting
+}
+
+export function setIsQuitting(value: boolean): void {
+  isQuitting = value
+}
+
+export function setupLifecycle(): void {
+  app.on('before-quit', () => {
+    logger.info('[lifecycle] before-quit')
+    isQuitting = true
+  })
+
+  app.on('will-quit', () => {
+    logger.info('[lifecycle] will-quit — flushing config')
+    try {
+      const configService = getConfigService()
+      if (configService) {
+        // electron-store는 동기적으로 디스크에 쓰므로 별도 flush 불필요
+        logger.info('[lifecycle] config flush complete')
+      }
+    } catch (error) {
+      logger.warn('[lifecycle] config flush failed:', error)
+    }
+  })
+}

src/main/services/AudioCaptureService.ts

@@ -0,0 +1,365 @@
+// src/main/services/AudioCaptureService.ts
+// 마이크 PCM 캡처 서비스. 설계서 01의 IAudioCaptureService 구현.
+// node-record-lpcm16 + SoX로 PCM16 16kHz mono 캡처.
+
+import { EventEmitter } from 'events'
+import { record } from 'node-record-lpcm16'
+import type { Recording } from 'node-record-lpcm16'
+import type { Readable } from 'stream'
+import { getLogger } from './LoggerService'
+import { configGet } from './ConfigService'
+import type { AudioDevice } from '@shared/types'
+import { AUDIO_FORMAT, TIMING } from '@shared/constants'
+import { D3ROError, ErrorCode } from '@shared/errors'
+
+const logger = getLogger('AudioCaptureService')
+
+/** 60ms 프레임 크기 (바이트): 16000 * 2 * 0.06 = 1920 */
+const FRAME_SIZE_BYTES = (AUDIO_FORMAT.SAMPLE_RATE * AUDIO_FORMAT.BYTES_PER_SAMPLE * 60) / 1000
+
+export type CaptureState = 'idle' | 'starting' | 'capturing' | 'stopping' | 'error'
+
+interface AudioCaptureEvents {
+  'audio-data': (payload: { buffer: Buffer; timestamp: number }) => void
+  'audio-level': (payload: { level: number; timestamp: number }) => void
+  'device-changed': (payload: {
+    previous: AudioDevice | null
+    current: AudioDevice
+  }) => void
+  started: (payload: { deviceId: string }) => void
+  stopped: (payload: { reason: 'manual' | 'device-lost' | 'error' }) => void
+  error: (payload: { error: D3ROError }) => void
+}
+
+/**
+ * PCM16 버퍼에서 RMS(Root Mean Square) 오디오 레벨을 계산한다.
+ * 반환값은 0.0 ~ 1.0 범위로 정규화된다.
+ */
+function calculateRMS(buffer: Buffer): number {
+  const samples = buffer.length / AUDIO_FORMAT.BYTES_PER_SAMPLE
+  if (samples === 0) return 0
+
+  let sumSquares = 0
+  for (let i = 0; i < buffer.length; i += AUDIO_FORMAT.BYTES_PER_SAMPLE) {
+    const sample = buffer.readInt16LE(i)
+    sumSquares += sample * sample
+  }
+
+  const rms = Math.sqrt(sumSquares / samples)
+  // PCM16 최대값 32768로 나눠서 0.0~1.0 범위로 정규화
+  return Math.min(1.0, rms / 32768)
+}
+
+class AudioCaptureService extends EventEmitter {
+  private _state: CaptureState = 'idle'
+  private _currentDevice: AudioDevice | null = null
+  private _refCount = 0
+  private _recording: Recording | null = null
+  private _stream: Readable | null = null
+  private _levelInterval: ReturnType<typeof setInterval> | null = null
+
+  /** 프레임 조립용 잔여 바이트 버퍼 */
+  private _residualBuffer: Buffer = Buffer.alloc(0)
+
+  /** RMS 계산용 누적 버퍼 (100ms 간격 emit) */
+  private _levelAccumulator: Buffer[] = []
+
+  get state(): CaptureState {
+    return this._state
+  }
+
+  get currentDevice(): AudioDevice | null {
+    return this._currentDevice
+  }
+
+  async start(deviceId?: string): Promise<void> {
+    if (this._state === 'capturing') {
+      this._refCount++
+      logger.debug(`Reference count increased to ${this._refCount}`)
+      return
+    }
+
+    if (this._state !== 'idle' && this._state !== 'error') {
+      logger.warn(`Cannot start capture in state: ${this._state}`)
+      return
+    }
+
+    this._state = 'starting'
+    const selectedDeviceId = deviceId ?? configGet('selectedDeviceId')
+
+    try {
+      logger.info(
+        `Starting audio capture (device: ${selectedDeviceId ?? 'default'}, ` +
+          `format: ${AUDIO_FORMAT.SAMPLE_RATE}Hz ${AUDIO_FORMAT.CHANNELS}ch ${AUDIO_FORMAT.BIT_DEPTH}bit)`
+      )
+
+      // node-record-lpcm16 으로 SoX rec 프로세스 spawn
+      const recordingOptions: Record<string, unknown> = {
+        sampleRate: AUDIO_FORMAT.SAMPLE_RATE,
+        channels: AUDIO_FORMAT.CHANNELS,
+        recorder: 'sox',
+        audioType: 'raw', // 헤더 없는 PCM raw 출력
+        endOnSilence: false
+      }
+
+      // 특정 디바이스가 지정된 경우 AUDIODEV 환경변수로 전달
+      if (selectedDeviceId && selectedDeviceId !== 'default') {
+        recordingOptions.device = selectedDeviceId
+      }
+
+      this._recording = record(recordingOptions)
+      this._stream = this._recording.stream()
+      this._residualBuffer = Buffer.alloc(0)
+      this._levelAccumulator = []
+
+      // 스트림 데이터 수신: 60ms 프레임 단위로 잘라 emit
+      this._stream.on('data', (chunk: Buffer) => {
+        this._onAudioChunk(chunk)
+      })
+
+      // 스트림 에러 처리
+      this._stream.on('error', (errorMessage: string | Error) => {
+        const msg = typeof errorMessage === 'string' ? errorMessage : errorMessage.message
+        logger.error(`Audio stream error: ${msg}`)
+
+        // SoX 미설치 감지
+        const isSoxMissing =
+          msg.includes('ENOENT') ||
+          msg.includes('not found') ||
+          msg.includes('is not recognized')
+
+        const errorCode = isSoxMissing
+          ? ErrorCode.AudioCaptureStartFailed
+          : ErrorCode.AudioStreamError
+
+        const d3roError = new D3ROError(
+          errorCode,
+          isSoxMissing
+            ? 'SoX가 설치되어 있지 않거나 PATH에 없습니다. SoX를 설치해주세요: https://sox.sourceforge.net'
+            : `Audio stream error: ${msg}`
+        )
+
+        this._handleError(d3roError, 'error')
+      })
+
+      // SoX 프로세스 종료 감지
+      this._stream.on('end', () => {
+        if (this._state === 'capturing') {
+          logger.warn('Audio stream ended unexpectedly')
+          this._handleError(
+            new D3ROError(ErrorCode.AudioCaptureFailed, 'Audio capture process terminated unexpectedly'),
+            'device-lost'
+          )
+        }
+      })
+
+      // SoX child process 에러 이벤트 (spawn 실패 등)
+      if (this._recording.process) {
+        this._recording.process.on('error', (err: Error) => {
+          logger.error(`SoX process spawn error: ${err.message}`)
+
+          const d3roError = new D3ROError(
+            ErrorCode.AudioCaptureStartFailed,
+            `SoX 프로세스 시작 실패: ${err.message}. SoX가 설치되어 있는지 확인해주세요.`
+          )
+
+          this._handleError(d3roError, 'error')
+        })
+      }
+
+      this._currentDevice = {
+        deviceId: selectedDeviceId ?? 'default',
+        label: 'Default Microphone',
+        isDefault: !selectedDeviceId || selectedDeviceId === 'default'
+      }
+
+      this._state = 'capturing'
+      this._refCount = 1
+
+      // 100ms 간격으로 audio-level 이벤트 emit
+      this._levelInterval = setInterval(() => {
+        this._emitAudioLevel()
+      }, TIMING.AUDIO_LEVEL_INTERVAL)
+
+      this.emit('started', { deviceId: this._currentDevice.deviceId })
+      logger.info('Audio capture started')
+    } catch (error) {
+      this._state = 'error'
+      const d3roError = new D3ROError(
+        ErrorCode.AudioCaptureStartFailed,
+        `Failed to start audio capture: ${error instanceof Error ? error.message : String(error)}`
+      )
+      this.emit('error', { error: d3roError })
+      throw d3roError
+    }
+  }
+
+  async stop(): Promise<void> {
+    if (this._state !== 'capturing') {
+      return
+    }
+
+    this._refCount--
+    if (this._refCount > 0) {
+      logger.debug(`Reference count decreased to ${this._refCount}`)
+      return
+    }
+
+    this._state = 'stopping'
+    this._cleanup()
+    this._state = 'idle'
+    this._currentDevice = null
+    this.emit('stopped', { reason: 'manual' })
+    logger.info('Audio capture stopped')
+  }
+
+  async getDevices(): Promise<AudioDevice[]> {
+    // 현재 Phase에서는 기본 디바이스만 반환. 실제 디바이스 열거는 추후.
+    logger.debug('Getting audio devices (default only)')
+    return [
+      {
+        deviceId: 'default',
+        label: 'Default Microphone',
+        isDefault: true
+      }
+    ]
+  }
+
+  getCurrentDevice(): AudioDevice | null {
+    return this._currentDevice
+  }
+
+  dispose(): void {
+    this._cleanup()
+    this._state = 'idle'
+    this._currentDevice = null
+    this._refCount = 0
+    this.removeAllListeners()
+    logger.info('AudioCaptureService disposed')
+  }
+
+  /**
+   * 수신된 오디오 청크를 60ms 프레임(1920 bytes) 단위로 분할하여 emit한다.
+   * 잔여 바이트는 다음 청크와 결합한다.
+   */
+  private _onAudioChunk(chunk: Buffer): void {
+    // 잔여 버퍼와 새 청크를 결합
+    const combined = this._residualBuffer.length > 0
+      ? Buffer.concat([this._residualBuffer, chunk])
+      : chunk
+
+    let offset = 0
+
+    // 60ms 프레임 단위로 분할하여 emit
+    while (offset + FRAME_SIZE_BYTES <= combined.length) {
+      const frame = combined.subarray(offset, offset + FRAME_SIZE_BYTES)
+      offset += FRAME_SIZE_BYTES
+
+      this.emit('audio-data', {
+        buffer: Buffer.from(frame), // 방어적 복사
+        timestamp: Date.now()
+      })
+
+      // RMS 계산용 누적
+      this._levelAccumulator.push(frame)
+    }
+
+    // 남은 바이트는 잔여 버퍼에 보관
+    if (offset < combined.length) {
+      this._residualBuffer = Buffer.from(combined.subarray(offset))
+    } else {
+      this._residualBuffer = Buffer.alloc(0)
+    }
+  }
+
+  /**
+   * 100ms 간격으로 누적된 오디오 데이터의 RMS 레벨을 계산하여 emit한다.
+   */
+  private _emitAudioLevel(): void {
+    if (this._levelAccumulator.length === 0) {
+      this.emit('audio-level', { level: 0, timestamp: Date.now() })
+      return
+    }
+
+    // 누적된 프레임들을 하나로 합쳐서 RMS 계산
+    const combined = Buffer.concat(this._levelAccumulator)
+    this._levelAccumulator = []
+
+    const level = calculateRMS(combined)
+    this.emit('audio-level', { level, timestamp: Date.now() })
+  }
+
+  /**
+   * 에러 발생 시 리소스 정리 + 에러 이벤트 emit.
+   */
+  private _handleError(error: D3ROError, stopReason: 'device-lost' | 'error'): void {
+    if (this._state === 'idle' || this._state === 'stopping') {
+      return
+    }
+
+    this._cleanup()
+    this._state = 'error'
+    this._currentDevice = null
+    this.emit('error', { error })
+    this.emit('stopped', { reason: stopReason })
+  }
+
+  /**
+   * 녹음 프로세스와 타이머를 정리한다.
+   */
+  private _cleanup(): void {
+    if (this._levelInterval) {
+      clearInterval(this._levelInterval)
+      this._levelInterval = null
+    }
+
+    if (this._stream) {
+      this._stream.removeAllListeners()
+      this._stream = null
+    }
+
+    if (this._recording) {
+      try {
+        this._recording.stop()
+      } catch {
+        // 이미 종료된 프로세스 kill 시 에러 무시
+      }
+      this._recording = null
+    }
+
+    this._residualBuffer = Buffer.alloc(0)
+    this._levelAccumulator = []
+  }
+
+  // EventEmitter 타입 오버라이드
+  override on<K extends keyof AudioCaptureEvents>(
+    event: K,
+    listener: AudioCaptureEvents[K]
+  ): this {
+    return super.on(event, listener)
+  }
+
+  override off<K extends keyof AudioCaptureEvents>(
+    event: K,
+    listener: AudioCaptureEvents[K]
+  ): this {
+    return super.off(event, listener)
+  }
+
+  override emit<K extends keyof AudioCaptureEvents>(
+    event: K,
+    ...args: Parameters<AudioCaptureEvents[K]>
+  ): boolean {
+    return super.emit(event, ...args)
+  }
+}
+
+// 싱글톤
+let instance: AudioCaptureService | null = null
+
+export function getAudioCaptureService(): AudioCaptureService {
+  if (!instance) {
+    instance = new AudioCaptureService()
+  }
+  return instance
+}

src/main/services/ConfigService.ts

@@ -0,0 +1,119 @@
+// src/main/services/ConfigService.ts
+// electron-store 기반 설정 관리. 설계서 02의 AppConfig 타입 사용.
+
+import { EventEmitter } from 'events'
+import type { AppConfig, ConfigChangedEvent } from '@shared/types'
+import { getLogger } from './LoggerService'
+
+const logger = getLogger('ConfigService')
+
+// electron-store v10은 ESM 전용이므로 동적 import 필요
+interface ElectronStore<T extends Record<string, unknown>> {
+  get<K extends keyof T>(key: K): T[K]
+  set<K extends keyof T>(key: K, value: T[K]): void
+  store: T
+}
+
+const CONFIG_DEFAULTS: AppConfig = {
+  theme: 'auto',
+  language: 'ko',
+  closeToTray: true,
+  autoLaunch: false,
+  soundEnabled: true,
+  selectedDeviceId: null,
+  sttModelId: 'base',
+  sttLanguage: 'auto',
+  ttsVoiceId: null,
+  ttsSpeed: 1.0,
+  ollamaServerUrl: 'http://localhost:11434',
+  llmModelId: null,
+  defaultLLMAction: 'refine',
+  dictationShortcut: {
+    keyCode: 0xa5, // Right Alt
+    ctrl: false,
+    alt: false,
+    shift: false,
+    meta: false,
+    displayLabel: 'Right Alt'
+  },
+  handsFreeShortcut: {
+    keyCode: 0xa5,
+    ctrl: false,
+    alt: false,
+    shift: false,
+    meta: false,
+    displayLabel: 'Right Alt (double)'
+  },
+  commandShortcut: {
+    keyCode: 0xa5,
+    ctrl: true,
+    alt: false,
+    shift: false,
+    meta: false,
+    displayLabel: 'Ctrl + Right Alt'
+  },
+  hotkeyEnabled: true,
+  insertMethod: 'clipboard',
+  autoInsert: true,
+  maxHistoryEntries: 1000
+}
+
+let store: ElectronStore<AppConfig> | null = null
+const emitter = new EventEmitter()
+
+export async function initConfigService(): Promise<void> {
+  const { default: Store } = await import('electron-store')
+  store = new Store<AppConfig>({
+    name: 'd3ro-voice-config',
+    defaults: CONFIG_DEFAULTS
+  })
+  logger.info('ConfigService initialized')
+}
+
+export function getConfigService(): ElectronStore<AppConfig> | null {
+  return store
+}
+
+export function configGet<K extends keyof AppConfig>(key: K): AppConfig[K] {
+  if (!store) {
+    logger.warn(`ConfigService not initialized, returning default for "${key}"`)
+    return CONFIG_DEFAULTS[key]
+  }
+  return store.get(key)
+}
+
+export function configSet<K extends keyof AppConfig>(key: K, value: AppConfig[K]): void {
+  if (!store) {
+    logger.warn(`ConfigService not initialized, cannot set "${key}"`)
+    return
+  }
+  const previousValue = store.get(key)
+  store.set(key, value)
+
+  const event: ConfigChangedEvent = {
+    key,
+    value,
+    previousValue
+  }
+  emitter.emit('config-changed', event)
+  logger.debug(`Config changed: ${key}`)
+}
+
+export function configGetAll(): AppConfig {
+  if (!store) return { ...CONFIG_DEFAULTS }
+  return store.store
+}
+
+export function configReset(key?: keyof AppConfig): void {
+  if (!store) return
+  if (key) {
+    store.set(key, CONFIG_DEFAULTS[key])
+  } else {
+    store.store = { ...CONFIG_DEFAULTS }
+  }
+}
+
+export function onConfigChanged(callback: (event: ConfigChangedEvent) => void): () => void {
+  emitter.on('config-changed', callback)
+  return () => emitter.off('config-changed', callback)
+}

src/main/services/HotkeyService.ts

@@ -0,0 +1,536 @@
+// src/main/services/HotkeyService.ts
+// uiohook-napi 기반 글로벌 키보드 후킹 서비스.
+// 설계서 01의 IHotkeyService 구현. Speakly HotkeyService + HotkeyConfig 패턴 참조.
+
+import { EventEmitter } from 'events'
+import { uIOhook, UiohookKey } from 'uiohook-napi'
+import type { UiohookKeyboardEvent } from 'uiohook-napi'
+import { getLogger } from './LoggerService'
+import { configGet } from './ConfigService'
+import { D3ROError, ErrorCode } from '@shared/errors'
+import { TIMING } from '@shared/constants'
+import type { HotkeyBinding } from '@shared/types'
+
+const logger = getLogger('HotkeyService')
+
+// ============================================================
+// 내부 타입
+// ============================================================
+
+export interface HotkeyConfig {
+  /** 핫키 식별자 (예: 'voice-dictation', 'voice-handsfree') */
+  id: string
+  /** uiohook 키코드 */
+  keyCode: number
+  /** 수정자 키 목록 */
+  modifiers: HotkeyModifier[]
+  /** true=hold-to-talk (누르고 있는 동안 활성), false=toggle */
+  holdMode: boolean
+  /** 더블프레스 감지 활성화 여부 */
+  doublePressEnabled: boolean
+  /** 활성화 여부 */
+  enabled: boolean
+}
+
+export type HotkeyModifier = 'ctrl' | 'alt' | 'shift' | 'meta'
+
+interface HotkeyServiceEvents {
+  'hotkey-pressed': (payload: { config: HotkeyConfig; timestamp: number }) => void
+  'hotkey-released': (payload: {
+    config: HotkeyConfig
+    durationMs: number
+    timestamp: number
+  }) => void
+  'double-press': (payload: {
+    config: HotkeyConfig
+    intervalMs: number
+    timestamp: number
+  }) => void
+  error: (payload: { error: D3ROError }) => void
+}
+
+// ============================================================
+// Windows VK 코드 → uiohook 키코드 매핑
+// ============================================================
+
+/**
+ * Windows Virtual-Key 코드를 uiohook-napi 키코드로 변환한다.
+ * ConfigService에 저장된 HotkeyBinding.keyCode는 Windows VK 코드이므로
+ * uiohook 이벤트와 비교하려면 변환이 필요하다.
+ */
+const VK_TO_UIOHOOK: ReadonlyMap<number, number> = new Map([
+  // 수정자 키
+  [0xa0, UiohookKey.Shift], // VK_LSHIFT
+  [0xa1, UiohookKey.ShiftRight], // VK_RSHIFT
+  [0xa2, UiohookKey.Ctrl], // VK_LCONTROL
+  [0xa3, UiohookKey.CtrlRight], // VK_RCONTROL
+  [0xa4, UiohookKey.Alt], // VK_LMENU
+  [0xa5, UiohookKey.AltRight], // VK_RMENU (Right Alt)
+  [0x5b, UiohookKey.Meta], // VK_LWIN
+  [0x5c, UiohookKey.MetaRight], // VK_RWIN
+
+  // 기능 키
+  [0x70, UiohookKey.F1],
+  [0x71, UiohookKey.F2],
+  [0x72, UiohookKey.F3],
+  [0x73, UiohookKey.F4],
+  [0x74, UiohookKey.F5],
+  [0x75, UiohookKey.F6],
+  [0x76, UiohookKey.F7],
+  [0x77, UiohookKey.F8],
+  [0x78, UiohookKey.F9],
+  [0x79, UiohookKey.F10],
+  [0x7a, UiohookKey.F11],
+  [0x7b, UiohookKey.F12],
+
+  // 일반 키
+  [0x20, UiohookKey.Space],
+  [0x0d, UiohookKey.Enter],
+  [0x1b, UiohookKey.Escape],
+  [0x08, UiohookKey.Backspace],
+  [0x09, UiohookKey.Tab],
+  [0x2d, UiohookKey.Insert],
+  [0x2e, UiohookKey.Delete],
+  [0x24, UiohookKey.Home],
+  [0x23, UiohookKey.End],
+  [0x21, UiohookKey.PageUp],
+  [0x22, UiohookKey.PageDown],
+  [0x25, UiohookKey.ArrowLeft],
+  [0x26, UiohookKey.ArrowUp],
+  [0x27, UiohookKey.ArrowRight],
+  [0x28, UiohookKey.ArrowDown],
+
+  // 알파벳 (VK_A=0x41 ~ VK_Z=0x5A)
+  [0x41, UiohookKey.A],
+  [0x42, UiohookKey.B],
+  [0x43, UiohookKey.C],
+  [0x44, UiohookKey.D],
+  [0x45, UiohookKey.E],
+  [0x46, UiohookKey.F],
+  [0x47, UiohookKey.G],
+  [0x48, UiohookKey.H],
+  [0x49, UiohookKey.I],
+  [0x4a, UiohookKey.J],
+  [0x4b, UiohookKey.K],
+  [0x4c, UiohookKey.L],
+  [0x4d, UiohookKey.M],
+  [0x4e, UiohookKey.N],
+  [0x4f, UiohookKey.O],
+  [0x50, UiohookKey.P],
+  [0x51, UiohookKey.Q],
+  [0x52, UiohookKey.R],
+  [0x53, UiohookKey.S],
+  [0x54, UiohookKey.T],
+  [0x55, UiohookKey.U],
+  [0x56, UiohookKey.V],
+  [0x57, UiohookKey.W],
+  [0x58, UiohookKey.X],
+  [0x59, UiohookKey.Y],
+  [0x5a, UiohookKey.Z],
+
+  // 숫자 (VK_0=0x30 ~ VK_9=0x39)
+  [0x30, UiohookKey['0']],
+  [0x31, UiohookKey['1']],
+  [0x32, UiohookKey['2']],
+  [0x33, UiohookKey['3']],
+  [0x34, UiohookKey['4']],
+  [0x35, UiohookKey['5']],
+  [0x36, UiohookKey['6']],
+  [0x37, UiohookKey['7']],
+  [0x38, UiohookKey['8']],
+  [0x39, UiohookKey['9']]
+])
+
+/**
+ * HotkeyBinding(Windows VK 코드)을 HotkeyConfig(uiohook 키코드)로 변환한다.
+ */
+function bindingToConfig(
+  id: string,
+  binding: HotkeyBinding,
+  holdMode: boolean,
+  doublePressEnabled: boolean
+): HotkeyConfig {
+  const uiohookKeyCode = VK_TO_UIOHOOK.get(binding.keyCode)
+
+  if (uiohookKeyCode === undefined) {
+    logger.warn(
+      `Unknown VK code 0x${binding.keyCode.toString(16)} for hotkey "${id}", ` +
+        `using raw value ${binding.keyCode}`
+    )
+  }
+
+  const modifiers: HotkeyModifier[] = []
+  if (binding.ctrl) modifiers.push('ctrl')
+  if (binding.alt) modifiers.push('alt')
+  if (binding.shift) modifiers.push('shift')
+  if (binding.meta) modifiers.push('meta')
+
+  return {
+    id,
+    keyCode: uiohookKeyCode ?? binding.keyCode,
+    modifiers,
+    holdMode,
+    doublePressEnabled,
+    enabled: true
+  }
+}
+
+// ============================================================
+// HotkeyService 클래스
+// ============================================================
+
+class HotkeyService extends EventEmitter {
+  private _isRunning = false
+  private _registeredHotkeys: Map<string, HotkeyConfig> = new Map()
+
+  /** 더블프레스 감지용: 마지막 press 시각 */
+  private _lastPressTime: Map<string, number> = new Map()
+
+  /** hold duration 계산용: press 시작 시각 */
+  private _pressStartTime: Map<string, number> = new Map()
+
+  /** 키 반복(auto-repeat) 방지: 현재 눌려있는 키 */
+  private _isKeyDown: Map<string, boolean> = new Map()
+
+  /** uiohook 이벤트 핸들러 (바인딩 해제용) */
+  private _onKeyDown: ((e: UiohookKeyboardEvent) => void) | null = null
+  private _onKeyUp: ((e: UiohookKeyboardEvent) => void) | null = null
+
+  get isRunning(): boolean {
+    return this._isRunning
+  }
+
+  get registeredHotkeys(): ReadonlyMap<string, HotkeyConfig> {
+    return this._registeredHotkeys
+  }
+
+  /**
+   * uiohook 글로벌 키보드 후킹을 시작한다.
+   * 이미 실행 중이면 무시.
+   */
+  start(): void {
+    if (this._isRunning) {
+      logger.warn('HotkeyService already running')
+      return
+    }
+
+    try {
+      this._onKeyDown = (e: UiohookKeyboardEvent) => this._handleKeyDown(e)
+      this._onKeyUp = (e: UiohookKeyboardEvent) => this._handleKeyUp(e)
+
+      uIOhook.on('keydown', this._onKeyDown)
+      uIOhook.on('keyup', this._onKeyUp)
+      uIOhook.start()
+
+      this._isRunning = true
+      logger.info('uiohook started, global keyboard hook active')
+    } catch (error) {
+      const d3roError = new D3ROError(
+        ErrorCode.HotkeyHookInitFailed,
+        `Failed to start uiohook: ${error instanceof Error ? error.message : String(error)}`
+      )
+      this.emit('error', { error: d3roError })
+      logger.error(d3roError.message)
+    }
+  }
+
+  /**
+   * uiohook 글로벌 키보드 후킹을 중지한다.
+   */
+  stop(): void {
+    if (!this._isRunning) {
+      return
+    }
+
+    try {
+      uIOhook.stop()
+
+      if (this._onKeyDown) {
+        uIOhook.removeListener('keydown', this._onKeyDown)
+        this._onKeyDown = null
+      }
+      if (this._onKeyUp) {
+        uIOhook.removeListener('keyup', this._onKeyUp)
+        this._onKeyUp = null
+      }
+
+      this._isRunning = false
+      this._isKeyDown.clear()
+      this._pressStartTime.clear()
+      logger.info('uiohook stopped')
+    } catch (error) {
+      logger.error(
+        `Failed to stop uiohook: ${error instanceof Error ? error.message : String(error)}`
+      )
+    }
+  }
+
+  /**
+   * 핫키를 등록한다. 동일 ID가 이미 등록되어 있으면 갱신한다.
+   */
+  registerHotkey(config: HotkeyConfig): void {
+    if (!config.enabled) {
+      logger.debug(`Hotkey "${config.id}" is disabled, skipping registration`)
+      return
+    }
+
+    this._registeredHotkeys.set(config.id, config)
+    logger.info(
+      `Hotkey registered: "${config.id}" ` +
+        `(keyCode=${config.keyCode}, modifiers=[${config.modifiers.join(',')}], ` +
+        `holdMode=${config.holdMode}, doublePress=${config.doublePressEnabled})`
+    )
+  }
+
+  /**
+   * 핫키 등록을 해제한다.
+   */
+  unregisterHotkey(id: string): void {
+    if (this._registeredHotkeys.delete(id)) {
+      this._lastPressTime.delete(id)
+      this._pressStartTime.delete(id)
+      this._isKeyDown.delete(id)
+      logger.info(`Hotkey unregistered: "${id}"`)
+    }
+  }
+
+  /**
+   * ConfigService에서 핫키 설정을 로드하여 등록한다.
+   */
+  loadFromConfig(): void {
+    const hotkeyEnabled = configGet('hotkeyEnabled')
+    if (!hotkeyEnabled) {
+      logger.info('Hotkeys disabled in config')
+      return
+    }
+
+    const dictationBinding = configGet('dictationShortcut')
+    const handsFreeBinding = configGet('handsFreeShortcut')
+    const commandBinding = configGet('commandShortcut')
+
+    // 기존 핫키 초기화
+    this._registeredHotkeys.clear()
+
+    // Dictation: hold-to-talk, 더블프레스 비활성
+    this.registerHotkey(
+      bindingToConfig('voice-dictation', dictationBinding, true, false)
+    )
+
+    // Hands-free: toggle, 더블프레스 활성
+    this.registerHotkey(
+      bindingToConfig('voice-handsfree', handsFreeBinding, false, true)
+    )
+
+    // Command: toggle, 더블프레스 비활성
+    this.registerHotkey(
+      bindingToConfig('voice-command', commandBinding, false, false)
+    )
+
+    logger.info(
+      `Loaded ${this._registeredHotkeys.size} hotkeys from config`
+    )
+  }
+
+  /**
+   * 서비스 리소스를 정리한다.
+   */
+  dispose(): void {
+    this.stop()
+    this._registeredHotkeys.clear()
+    this._lastPressTime.clear()
+    this._pressStartTime.clear()
+    this._isKeyDown.clear()
+    this.removeAllListeners()
+    logger.info('HotkeyService disposed')
+  }
+
+  // ============================================================
+  // 내부: 키 이벤트 처리
+  // ============================================================
+
+  /**
+   * 키 다운 이벤트를 처리한다.
+   * 등록된 핫키 중 매칭되는 것을 찾아 적절한 이벤트를 발행한다.
+   */
+  private _handleKeyDown(e: UiohookKeyboardEvent): void {
+    const matched = this._findMatchingHotkey(e)
+    if (!matched) return
+
+    const { id } = matched
+
+    // 키 반복(auto-repeat) 무시: 이미 눌려있으면 건너뜀
+    if (this._isKeyDown.get(id)) {
+      return
+    }
+    this._isKeyDown.set(id, true)
+
+    const now = Date.now()
+
+    // press 시작 시각 기록 (hold duration 계산용)
+    this._pressStartTime.set(id, now)
+
+    // 더블프레스 감지
+    if (matched.doublePressEnabled) {
+      const lastPress = this._lastPressTime.get(id)
+
+      if (lastPress !== undefined && now - lastPress < TIMING.DOUBLE_PRESS_DURATION) {
+        // 300ms 이내 연속 두 번 press = 더블프레스
+        this._lastPressTime.delete(id)
+
+        logger.debug(`Double-press detected: "${id}" (interval=${now - lastPress}ms)`)
+        this.emit('double-press', {
+          config: matched,
+          intervalMs: now - lastPress,
+          timestamp: now
+        })
+        return
+      }
+
+      this._lastPressTime.set(id, now)
+    }
+
+    logger.debug(`Hotkey pressed: "${id}"`)
+    this.emit('hotkey-pressed', {
+      config: matched,
+      timestamp: now
+    })
+  }
+
+  /**
+   * 키 업 이벤트를 처리한다.
+   */
+  private _handleKeyUp(e: UiohookKeyboardEvent): void {
+    const matched = this._findMatchingHotkey(e)
+    if (!matched) return
+
+    const { id } = matched
+
+    // 눌려있지 않은 키의 release는 무시
+    if (!this._isKeyDown.get(id)) {
+      return
+    }
+    this._isKeyDown.set(id, false)
+
+    const now = Date.now()
+    const pressStart = this._pressStartTime.get(id)
+    const durationMs = pressStart !== undefined ? now - pressStart : 0
+    this._pressStartTime.delete(id)
+
+    logger.debug(`Hotkey released: "${id}" (duration=${durationMs}ms)`)
+    this.emit('hotkey-released', {
+      config: matched,
+      durationMs,
+      timestamp: now
+    })
+  }
+
+  /**
+   * uiohook 키 이벤트와 등록된 핫키를 매칭한다.
+   * 키코드와 수정자 키가 모두 일치해야 매칭 성공.
+   */
+  private _findMatchingHotkey(e: UiohookKeyboardEvent): HotkeyConfig | null {
+    for (const config of this._registeredHotkeys.values()) {
+      if (!config.enabled) continue
+
+      // 키코드 일치 확인
+      if (e.keycode !== config.keyCode) continue
+
+      // 수정자 키 일치 확인
+      // 핫키에 지정된 수정자가 모두 눌려 있어야 하고,
+      // 지정되지 않은 수정자는 눌려 있으면 안 된다.
+      //
+      // 단, 핫키의 주 키 자체가 수정자 키인 경우(예: Right Alt)에는
+      // 해당 수정자의 altKey 등이 true로 올 수 있으므로, 주 키가 수정자인 경우
+      // 해당 수정자 검사를 건너뛴다.
+      const isKeyModifier = this._isModifierKeyCode(config.keyCode)
+
+      const wantsCtrl = config.modifiers.includes('ctrl')
+      const wantsAlt = config.modifiers.includes('alt')
+      const wantsShift = config.modifiers.includes('shift')
+      const wantsMeta = config.modifiers.includes('meta')
+
+      const ctrlMatch = isKeyModifier && this._isCtrlKeyCode(config.keyCode)
+        ? true
+        : e.ctrlKey === wantsCtrl
+      const altMatch = isKeyModifier && this._isAltKeyCode(config.keyCode)
+        ? true
+        : e.altKey === wantsAlt
+      const shiftMatch = isKeyModifier && this._isShiftKeyCode(config.keyCode)
+        ? true
+        : e.shiftKey === wantsShift
+      const metaMatch = isKeyModifier && this._isMetaKeyCode(config.keyCode)
+        ? true
+        : e.metaKey === wantsMeta
+
+      if (ctrlMatch && altMatch && shiftMatch && metaMatch) {
+        return config
+      }
+    }
+
+    return null
+  }
+
+  /** 주어진 uiohook 키코드가 수정자 키(Ctrl/Alt/Shift/Meta)인지 확인 */
+  private _isModifierKeyCode(keyCode: number): boolean {
+    return (
+      this._isCtrlKeyCode(keyCode) ||
+      this._isAltKeyCode(keyCode) ||
+      this._isShiftKeyCode(keyCode) ||
+      this._isMetaKeyCode(keyCode)
+    )
+  }
+
+  private _isCtrlKeyCode(keyCode: number): boolean {
+    return keyCode === UiohookKey.Ctrl || keyCode === UiohookKey.CtrlRight
+  }
+
+  private _isAltKeyCode(keyCode: number): boolean {
+    return keyCode === UiohookKey.Alt || keyCode === UiohookKey.AltRight
+  }
+
+  private _isShiftKeyCode(keyCode: number): boolean {
+    return keyCode === UiohookKey.Shift || keyCode === UiohookKey.ShiftRight
+  }
+
+  private _isMetaKeyCode(keyCode: number): boolean {
+    return keyCode === UiohookKey.Meta || keyCode === UiohookKey.MetaRight
+  }
+
+  // ============================================================
+  // EventEmitter 타입 오버라이드
+  // ============================================================
+
+  override on<K extends keyof HotkeyServiceEvents>(
+    event: K,
+    listener: HotkeyServiceEvents[K]
+  ): this {
+    return super.on(event, listener)
+  }
+
+  override off<K extends keyof HotkeyServiceEvents>(
+    event: K,
+    listener: HotkeyServiceEvents[K]
+  ): this {
+    return super.off(event, listener)
+  }
+
+  override emit<K extends keyof HotkeyServiceEvents>(
+    event: K,
+    ...args: Parameters<HotkeyServiceEvents[K]>
+  ): boolean {
+    return super.emit(event, ...args)
+  }
+}
+
+// ============================================================
+// 싱글톤
+// ============================================================
+
+let instance: HotkeyService | null = null
+
+export function getHotkeyService(): HotkeyService {
+  if (!instance) {
+    instance = new HotkeyService()
+  }
+  return instance
+}

src/main/services/LocalSTTService.ts

@@ -0,0 +1,729 @@
+// src/main/services/LocalSTTService.ts
+// faster-whisper sidecar를 관리하고 오디오 버퍼를 텍스트로 변환한다.
+// 싱글톤 + EventEmitter 패턴. Speakly VoiceRecognitionService의
+// 상태 머신 및 이중 조건 플러시 패턴 적용.
+
+import { EventEmitter } from 'events'
+import { type ChildProcess, spawn } from 'child_process'
+import path from 'path'
+import { app } from 'electron'
+import { getLogger } from './LoggerService'
+import { configGet } from './ConfigService'
+import { D3ROError, ErrorCode } from '@shared/errors'
+import type { STTModel, STTStatus, STTEngineState } from '@shared/types'
+
+// ── 내부 타입 정의 ────────────────────────────────────────
+
+/** STT 엔진 상태 머신 */
+const enum STTState {
+  Uninitialized = 'uninitialized',
+  Loading = 'loading',
+  Ready = 'ready',
+  Transcribing = 'transcribing',
+  Error = 'error',
+}
+
+/** 전사 결과 세그먼트 */
+export interface TranscriptionSegment {
+  readonly text: string
+  readonly start: number
+  readonly end: number
+  readonly confidence: number
+}
+
+/** 전사 결과 */
+export interface TranscriptionResult {
+  readonly text: string
+  readonly segments: TranscriptionSegment[]
+  readonly language: string
+  readonly duration: number
+  readonly processingTime: number
+}
+
+/** 전사 옵션 */
+export interface TranscribeOptions {
+  language?: string
+  initialPrompt?: string
+  vadFilter?: boolean
+}
+
+/** sidecar /health 응답 */
+interface HealthResponse {
+  status: string
+  model: string | null
+  gpu: boolean
+}
+
+/** sidecar /load 응답 */
+interface LoadResponse {
+  status: string
+  model_id: string
+  load_time_ms: number
+}
+
+/** sidecar /transcribe 응답 */
+interface TranscribeResponse {
+  text: string
+  segments: Array<{
+    text: string
+    start: number
+    end: number
+    avg_logprob: number
+  }>
+  language: string
+  duration: number
+  processing_time: number
+}
+
+/** 이벤트 페이로드 */
+export interface LocalSTTEvents {
+  'transcription-delta': { text: string; isFinal: boolean }
+  'transcription-complete': { result: TranscriptionResult }
+  'model-loaded': { model: STTModel; loadTimeMs: number }
+  'error': { error: D3ROError }
+}
+
+// ── 상수 ──────────────────────────────────────────────────
+
+const SIDECAR_PORT = 18765
+const HEALTH_CHECK_INTERVAL_MS = 1000
+const HEALTH_CHECK_TIMEOUT_MS = 30000
+const MAX_RESTART_COUNT = 3
+const SIDECAR_REQUEST_TIMEOUT_MS = 120000
+
+/** 알려진 Whisper 모델 카탈로그 */
+const MODEL_CATALOG: STTModel[] = [
+  {
+    id: 'tiny',
+    name: 'Tiny',
+    sizeBytes: 75_000_000,
+    downloaded: false,
+    languages: ['auto', 'ko', 'en', 'ja', 'zh'],
+    accuracy: 1,
+    speed: 5,
+  },
+  {
+    id: 'base',
+    name: 'Base',
+    sizeBytes: 141_000_000,
+    downloaded: false,
+    languages: ['auto', 'ko', 'en', 'ja', 'zh'],
+    accuracy: 2,
+    speed: 4,
+  },
+  {
+    id: 'small',
+    name: 'Small',
+    sizeBytes: 466_000_000,
+    downloaded: false,
+    languages: ['auto', 'ko', 'en', 'ja', 'zh'],
+    accuracy: 3,
+    speed: 3,
+  },
+  {
+    id: 'medium',
+    name: 'Medium',
+    sizeBytes: 1_500_000_000,
+    downloaded: false,
+    languages: ['auto', 'ko', 'en', 'ja', 'zh'],
+    accuracy: 4,
+    speed: 2,
+  },
+  {
+    id: 'large-v3',
+    name: 'Large V3',
+    sizeBytes: 3_100_000_000,
+    downloaded: false,
+    languages: ['auto', 'ko', 'en', 'ja', 'zh'],
+    accuracy: 5,
+    speed: 1,
+  },
+]
+
+// ── 서비스 구현 ───────────────────────────────────────────
+
+const logger = getLogger('LocalSTTService')
+
+class LocalSTTService extends EventEmitter {
+  private _state: STTState = STTState.Uninitialized
+  private _sidecarProcess: ChildProcess | null = null
+  private _port: number = SIDECAR_PORT
+  private _currentModelId: string | null = null
+  private _restartCount: number = 0
+  private _disposed: boolean = false
+  private _gpuAccelerated: boolean = false
+
+  // ── 이중 조건 플러시 (Speakly 패턴) ──
+  private _modelReady: boolean = false
+  private _audioBuffer: Buffer[] = []
+  private _pendingResolve: ((result: TranscriptionResult) => void) | null = null
+  private _pendingReject: ((error: D3ROError) => void) | null = null
+  // errorEmitted 플래그로 이벤트 중복 방지
+  private _errorEmitted: boolean = false
+
+  // ── 상태 접근자 ──
+
+  get state(): STTState {
+    return this._state
+  }
+
+  get currentModelId(): string | null {
+    return this._currentModelId
+  }
+
+  // ── 공개 메서드 ──
+
+  /**
+   * Whisper sidecar 프로세스 시작 + 모델 로딩.
+   * 이미 로딩된 모델과 같으면 무시.
+   */
+  async initialize(modelId?: string): Promise<void> {
+    const targetModel = modelId ?? configGet('sttModelId')
+
+    if (this._disposed) {
+      throw new D3ROError(
+        ErrorCode.STTSidecarSpawnFailed,
+        'LocalSTTService가 이미 dispose되었습니다',
+      )
+    }
+
+    // 이미 같은 모델이 로딩된 상태면 무시
+    if (
+      this._state === STTState.Ready &&
+      this._currentModelId === targetModel
+    ) {
+      logger.debug(`모델 ${targetModel}이 이미 로딩되어 있습니다`)
+      return
+    }
+
+    this._setState(STTState.Loading)
+    this._errorEmitted = false
+
+    try {
+      // sidecar가 아직 실행 중이 아니면 시작
+      if (!this._sidecarProcess || this._sidecarProcess.exitCode !== null) {
+        await this._spawnSidecar()
+        await this._waitForHealth()
+      }
+
+      // 모델 로딩
+      await this._loadModel(targetModel)
+      this._currentModelId = targetModel
+      this._modelReady = true
+      this._setState(STTState.Ready)
+
+      // 이중 조건 플러시 시도
+      this._tryFlushAll()
+
+      logger.info(`STT 초기화 완료: 모델=${targetModel}`)
+    } catch (err) {
+      this._setState(STTState.Error)
+      const d3roErr =
+        err instanceof D3ROError
+          ? err
+          : new D3ROError(
+              ErrorCode.STTModelLoadFailed,
+              `STT 초기화 실패: ${err instanceof Error ? err.message : String(err)}`,
+            )
+      this._emitError(d3roErr)
+      throw d3roErr
+    }
+  }
+
+  /**
+   * 오디오 버퍼를 전사.
+   * PCM16 16kHz mono 포맷이어야 한다.
+   * 이중 조건 플러시: 모델 로딩과 오디오 버퍼링이 모두 완료되면 실행.
+   */
+  async transcribe(
+    audioBuffer: Buffer,
+    options?: TranscribeOptions,
+  ): Promise<TranscriptionResult> {
+    if (this._disposed) {
+      throw new D3ROError(
+        ErrorCode.STTTranscriptionFailed,
+        'LocalSTTService가 이미 dispose되었습니다',
+      )
+    }
+
+    if (audioBuffer.length === 0) {
+      throw new D3ROError(ErrorCode.STTNoAudioData, '오디오 데이터가 비어있습니다')
+    }
+
+    // 모델이 아직 준비되지 않았으면 버퍼에 적재하고 대기
+    if (!this._modelReady) {
+      logger.debug('모델 로딩 중, 오디오 버퍼에 적재')
+      this._audioBuffer.push(audioBuffer)
+
+      return new Promise<TranscriptionResult>((resolve, reject) => {
+        this._pendingResolve = resolve
+        this._pendingReject = reject
+        // 이중 조건 플러시 시도 (모델이 이미 준비되었을 수 있음)
+        this._tryFlushAll()
+      })
+    }
+
+    // 모델 준비 완료 상태: 직접 전사
+    return this._sendToSidecar(audioBuffer, options)
+  }
+
+  /**
+   * 다운로드된 모델 목록 조회.
+   * 실제 다운로드 여부는 sidecar에 위임 (faster-whisper가 자동 다운로드).
+   */
+  getModels(): STTModel[] {
+    return MODEL_CATALOG.map((m) => ({
+      ...m,
+      // 현재 로딩된 모델은 downloaded=true로 표시
+      downloaded: m.id === this._currentModelId ? true : m.downloaded,
+    }))
+  }
+
+  /** 현재 상태 조회 */
+  getStatus(): STTStatus {
+    const stateMap: Record<STTState, STTEngineState> = {
+      [STTState.Uninitialized]: 'not-installed' as STTEngineState,
+      [STTState.Loading]: 'loading' as STTEngineState,
+      [STTState.Ready]: 'ready' as STTEngineState,
+      [STTState.Transcribing]: 'processing' as STTEngineState,
+      [STTState.Error]: 'error' as STTEngineState,
+    }
+
+    return {
+      engineState: stateMap[this._state],
+      activeModel: this._currentModelId,
+      engineVersion: null,
+      gpuAccelerated: this._gpuAccelerated,
+    }
+  }
+
+  /** sidecar 프로세스 종료 및 리소스 정리 */
+  async dispose(): Promise<void> {
+    if (this._disposed) return
+    this._disposed = true
+
+    logger.info('LocalSTTService dispose 시작')
+
+    // pending promise를 reject
+    if (this._pendingReject) {
+      this._pendingReject(
+        new D3ROError(ErrorCode.STTTranscriptionCancelled, '서비스 종료로 전사 취소'),
+      )
+      this._pendingResolve = null
+      this._pendingReject = null
+    }
+
+    this._audioBuffer = []
+    this._modelReady = false
+
+    await this._shutdownSidecar()
+    this._setState(STTState.Uninitialized)
+
+    logger.info('LocalSTTService dispose 완료')
+  }
+
+  // ── 이중 조건 플러시 (Speakly 핵심 패턴) ──
+
+  /**
+   * 모델 로딩과 오디오 버퍼링이 모두 완료되면 실행.
+   * 설정 메시지(모델) 먼저, 오디오 데이터 후.
+   */
+  private _tryFlushAll(): void {
+    if (!this._modelReady) return
+    if (this._audioBuffer.length === 0) return
+    if (!this._pendingResolve) return
+
+    const merged = Buffer.concat(this._audioBuffer)
+    this._audioBuffer = []
+
+    const resolve = this._pendingResolve
+    const reject = this._pendingReject
+    this._pendingResolve = null
+    this._pendingReject = null
+
+    this._sendToSidecar(merged)
+      .then(resolve)
+      .catch((err: unknown) => {
+        if (reject) {
+          reject(
+            err instanceof D3ROError
+              ? err
+              : new D3ROError(
+                  ErrorCode.STTTranscriptionFailed,
+                  `전사 실패: ${err instanceof Error ? err.message : String(err)}`,
+                ),
+          )
+        }
+      })
+  }
+
+  // ── Sidecar 관리 ──
+
+  private _getSidecarPath(): string {
+    const basePath = app.isPackaged ? process.resourcesPath : app.getAppPath()
+    return path.join(basePath, 'sidecar', 'main.py')
+  }
+
+  private async _spawnSidecar(): Promise<void> {
+    const sidecarPath = this._getSidecarPath()
+    logger.info(`Sidecar 시작: python ${sidecarPath} --port ${this._port}`)
+
+    return new Promise<void>((resolve, reject) => {
+      const pythonCmd = process.platform === 'win32' ? 'python' : 'python3'
+
+      try {
+        this._sidecarProcess = spawn(
+          pythonCmd,
+          [sidecarPath, '--port', String(this._port)],
+          {
+            stdio: ['pipe', 'pipe', 'pipe'],
+            env: { ...process.env },
+          },
+        )
+      } catch (err) {
+        const d3roErr = new D3ROError(
+          ErrorCode.STTSidecarSpawnFailed,
+          `Sidecar 프로세스 생성 실패: ${err instanceof Error ? err.message : String(err)}`,
+        )
+        reject(d3roErr)
+        return
+      }
+
+      const sidecarLogger = getLogger('sidecar')
+
+      this._sidecarProcess.stdout?.on('data', (data: Buffer) => {
+        const text = data.toString().trim()
+        if (text) {
+          sidecarLogger.info(text)
+        }
+      })
+
+      this._sidecarProcess.stderr?.on('data', (data: Buffer) => {
+        const text = data.toString().trim()
+        if (text) {
+          sidecarLogger.warn(text)
+        }
+      })
+
+      this._sidecarProcess.on('error', (err: Error) => {
+        logger.error(`Sidecar 프로세스 에러: ${err.message}`)
+        reject(
+          new D3ROError(
+            ErrorCode.STTSidecarSpawnFailed,
+            `Sidecar 프로세스 에러: ${err.message}`,
+          ),
+        )
+      })
+
+      this._sidecarProcess.on('exit', (code: number | null, signal: string | null) => {
+        logger.warn(`Sidecar 프로세스 종료: code=${code}, signal=${signal}`)
+        this._sidecarProcess = null
+        this._modelReady = false
+
+        if (!this._disposed) {
+          this._handleSidecarCrash()
+        }
+      })
+
+      // spawn 자체는 비동기적이므로 즉시 resolve
+      // 실제 준비는 _waitForHealth에서 확인
+      resolve()
+    })
+  }
+
+  private async _waitForHealth(): Promise<void> {
+    const startTime = Date.now()
+
+    while (Date.now() - startTime < HEALTH_CHECK_TIMEOUT_MS) {
+      try {
+        const response = await fetch(`http://localhost:${this._port}/health`, {
+          signal: AbortSignal.timeout(2000),
+        })
+
+        if (response.ok) {
+          const data = (await response.json()) as HealthResponse
+          this._gpuAccelerated = data.gpu
+          logger.info(
+            `Sidecar 헬스체크 성공: status=${data.status}, gpu=${data.gpu}`,
+          )
+          return
+        }
+      } catch {
+        // 아직 준비 안 됨, 재시도
+      }
+
+      await this._sleep(HEALTH_CHECK_INTERVAL_MS)
+    }
+
+    throw new D3ROError(
+      ErrorCode.STTSidecarCommunicationFailed,
+      `Sidecar 헬스체크 타임아웃 (${HEALTH_CHECK_TIMEOUT_MS}ms)`,
+    )
+  }
+
+  private async _loadModel(modelId: string): Promise<void> {
+    logger.info(`모델 로딩 시작: ${modelId}`)
+    const startTime = Date.now()
+
+    const response = await fetch(`http://localhost:${this._port}/load`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ model_id: modelId }),
+      signal: AbortSignal.timeout(SIDECAR_REQUEST_TIMEOUT_MS),
+    })
+
+    if (!response.ok) {
+      const errorText = await response.text()
+      throw new D3ROError(
+        ErrorCode.STTModelLoadFailed,
+        `모델 로딩 실패 (HTTP ${response.status}): ${errorText}`,
+      )
+    }
+
+    const data = (await response.json()) as LoadResponse
+    const loadTimeMs = Date.now() - startTime
+
+    const model = MODEL_CATALOG.find((m) => m.id === modelId)
+    if (model) {
+      this.emit('model-loaded', {
+        model: { ...model, downloaded: true },
+        loadTimeMs,
+      })
+    }
+
+    logger.info(
+      `모델 로딩 완료: ${data.model_id}, ${loadTimeMs}ms`,
+    )
+  }
+
+  // ── HTTP 전사 요청 ──
+
+  private async _sendToSidecar(
+    audioBuffer: Buffer,
+    options?: TranscribeOptions,
+  ): Promise<TranscriptionResult> {
+    if (!this._sidecarProcess || this._sidecarProcess.exitCode !== null) {
+      throw new D3ROError(
+        ErrorCode.STTSidecarCommunicationFailed,
+        'Sidecar 프로세스가 실행 중이 아닙니다',
+      )
+    }
+
+    this._setState(STTState.Transcribing)
+    const startTime = Date.now()
+
+    try {
+      const language = options?.language ?? configGet('sttLanguage')
+      const vadFilter = options?.vadFilter ?? true
+      const initialPrompt = options?.initialPrompt ?? ''
+
+      // Node 18+ 내장 fetch + FormData + Blob으로 multipart 전송
+      const formData = new FormData()
+      // Buffer → ArrayBuffer 복사 후 Blob 생성 (Node/Electron 타입 호환)
+      const arrayBuf = audioBuffer.buffer.slice(
+        audioBuffer.byteOffset,
+        audioBuffer.byteOffset + audioBuffer.byteLength,
+      ) as ArrayBuffer
+      formData.append(
+        'audio',
+        new Blob([arrayBuf], { type: 'application/octet-stream' }),
+        'audio.pcm',
+      )
+      formData.append('language', language)
+      formData.append('vad_filter', String(vadFilter))
+      if (initialPrompt) {
+        formData.append('initial_prompt', initialPrompt)
+      }
+
+      const response = await fetch(
+        `http://localhost:${this._port}/transcribe`,
+        {
+          method: 'POST',
+          body: formData,
+          signal: AbortSignal.timeout(SIDECAR_REQUEST_TIMEOUT_MS),
+        },
+      )
+
+      if (!response.ok) {
+        const errorText = await response.text()
+        throw new D3ROError(
+          ErrorCode.STTTranscriptionFailed,
+          `전사 실패 (HTTP ${response.status}): ${errorText}`,
+        )
+      }
+
+      const data = (await response.json()) as TranscribeResponse
+      const processingTime = Date.now() - startTime
+
+      const result: TranscriptionResult = {
+        text: data.text,
+        segments: data.segments.map((seg) => ({
+          text: seg.text,
+          start: seg.start,
+          end: seg.end,
+          confidence: Math.exp(seg.avg_logprob),
+        })),
+        language: data.language,
+        duration: data.duration,
+        processingTime,
+      }
+
+      // 중간 결과 이벤트 (isFinal=true)
+      this.emit('transcription-delta', { text: result.text, isFinal: true })
+      this.emit('transcription-complete', { result })
+
+      this._setState(STTState.Ready)
+
+      logger.info(
+        `전사 완료: "${result.text.substring(0, 50)}..." (${processingTime}ms, lang=${result.language})`,
+      )
+
+      return result
+    } catch (err) {
+      this._setState(STTState.Ready) // 에러 후에도 Ready 복귀 (sidecar가 살아있으면)
+
+      if (err instanceof D3ROError) {
+        throw err
+      }
+
+      const message = err instanceof Error ? err.message : String(err)
+
+      // 타임아웃 구분
+      if (message.includes('abort') || message.includes('timeout')) {
+        throw new D3ROError(
+          ErrorCode.STTTranscriptionTimeout,
+          `전사 타임아웃: ${message}`,
+        )
+      }
+
+      throw new D3ROError(
+        ErrorCode.STTTranscriptionFailed,
+        `전사 실패: ${message}`,
+      )
+    }
+  }
+
+  // ── Sidecar Crash 처리 ──
+
+  private _handleSidecarCrash(): void {
+    if (this._disposed) return
+
+    this._restartCount++
+    logger.warn(`Sidecar crash 감지, 재시작 시도 ${this._restartCount}/${MAX_RESTART_COUNT}`)
+
+    if (this._restartCount > MAX_RESTART_COUNT) {
+      const err = new D3ROError(
+        ErrorCode.STTSidecarCrashed,
+        `Sidecar가 ${MAX_RESTART_COUNT}회 crash 후 재시작 포기`,
+      )
+      this._setState(STTState.Error)
+      this._emitError(err)
+
+      // pending promise reject
+      if (this._pendingReject) {
+        this._pendingReject(err)
+        this._pendingResolve = null
+        this._pendingReject = null
+      }
+      return
+    }
+
+    // 비동기 재시작
+    const modelToReload = this._currentModelId
+    this._currentModelId = null
+    this._modelReady = false
+
+    // setTimeout으로 이벤트 루프에 양보
+    setTimeout(() => {
+      if (this._disposed) return
+      this.initialize(modelToReload ?? undefined).catch((err: unknown) => {
+        logger.error(
+          `Sidecar 재시작 실패: ${err instanceof Error ? err.message : String(err)}`,
+        )
+      })
+    }, 1000 * this._restartCount) // 점진적 백오프
+  }
+
+  private async _shutdownSidecar(): Promise<void> {
+    if (!this._sidecarProcess || this._sidecarProcess.exitCode !== null) {
+      this._sidecarProcess = null
+      return
+    }
+
+    logger.info('Sidecar 종료 요청')
+
+    try {
+      // POST /shutdown 요청
+      await fetch(`http://localhost:${this._port}/shutdown`, {
+        method: 'POST',
+        signal: AbortSignal.timeout(3000),
+      })
+    } catch {
+      // 이미 종료되었거나 통신 불가 — 무시
+    }
+
+    // 프로세스가 아직 살아있으면 강제 종료
+    if (this._sidecarProcess && this._sidecarProcess.exitCode === null) {
+      logger.warn('Sidecar graceful shutdown 실패, SIGKILL 전송')
+      this._sidecarProcess.kill('SIGKILL')
+    }
+
+    this._sidecarProcess = null
+  }
+
+  // ── 내부 유틸 ──
+
+  private _setState(newState: STTState): void {
+    if (this._state === newState) return
+    const prev = this._state
+    this._state = newState
+    logger.debug(`STTState: ${prev} -> ${newState}`)
+  }
+
+  private _emitError(error: D3ROError): void {
+    if (this._errorEmitted) return
+    this._errorEmitted = true
+    this.emit('error', { error })
+    logger.error(`STT 에러: [${error.code}] ${error.message}`)
+  }
+
+  private _sleep(ms: number): Promise<void> {
+    return new Promise((resolve) => setTimeout(resolve, ms))
+  }
+
+  // ── 타입 안전한 이벤트 메서드 오버라이드 ──
+
+  override emit<K extends keyof LocalSTTEvents>(
+    event: K,
+    payload: LocalSTTEvents[K],
+  ): boolean {
+    return super.emit(event, payload)
+  }
+
+  override on<K extends keyof LocalSTTEvents>(
+    event: K,
+    listener: (payload: LocalSTTEvents[K]) => void,
+  ): this {
+    return super.on(event, listener)
+  }
+
+  override off<K extends keyof LocalSTTEvents>(
+    event: K,
+    listener: (payload: LocalSTTEvents[K]) => void,
+  ): this {
+    return super.off(event, listener)
+  }
+}
+
+// ── 싱글톤 ──
+
+let instance: LocalSTTService | null = null
+
+export function getLocalSTTService(): LocalSTTService {
+  if (!instance) {
+    instance = new LocalSTTService()
+  }
+  return instance
+}
+
+export { LocalSTTService, STTState }

src/main/services/LoggerService.ts

@@ -0,0 +1,32 @@
+// src/main/services/LoggerService.ts
+// electron-log 래퍼. 카테고리별 로깅을 지원한다.
+
+import log from 'electron-log'
+
+export interface CategoryLogger {
+  info(message: string, ...args: unknown[]): void
+  warn(message: string, ...args: unknown[]): void
+  error(message: string, ...args: unknown[]): void
+  debug(message: string, ...args: unknown[]): void
+}
+
+let initialized = false
+
+export function initLoggerService(): void {
+  if (initialized) return
+  initialized = true
+
+  log.transports.file.maxSize = 5 * 1024 * 1024 // 5MB
+  log.transports.file.format = '[{y}-{m}-{d} {h}:{i}:{s}.{ms}] [{level}] {text}'
+  log.transports.console.format = '[{h}:{i}:{s}.{ms}] [{level}] {text}'
+}
+
+export function getLogger(category: string): CategoryLogger {
+  const prefix = `[${category}]`
+  return {
+    info: (message: string, ...args: unknown[]) => log.info(`${prefix} ${message}`, ...args),
+    warn: (message: string, ...args: unknown[]) => log.warn(`${prefix} ${message}`, ...args),
+    error: (message: string, ...args: unknown[]) => log.error(`${prefix} ${message}`, ...args),
+    debug: (message: string, ...args: unknown[]) => log.debug(`${prefix} ${message}`, ...args)
+  }
+}

src/main/services/VoiceModeService.ts

@@ -0,0 +1,625 @@
+// src/main/services/VoiceModeService.ts
+// 전체 음성 파이프라인 오케스트레이터.
+// 설계서 01의 IVoiceModeService 구현. Speakly VoiceModeService의
+// 상태 머신, 이중 조건 플러시, Action Queue 패턴 적용.
+
+import { EventEmitter } from 'events'
+import { randomUUID } from 'crypto'
+import { getLogger } from './LoggerService'
+import { getAudioCaptureService } from './AudioCaptureService'
+import { getLocalSTTService } from './LocalSTTService'
+import type { TranscriptionResult } from './LocalSTTService'
+import { getHotkeyService } from './HotkeyService'
+import type { HotkeyConfig } from './HotkeyService'
+import { configGet } from './ConfigService'
+import { D3ROError, ErrorCode } from '@shared/errors'
+import { TIMING } from '@shared/constants'
+import { RecognitionState, AudioState } from '@shared/types'
+import type { VoiceMode, VoiceState } from '@shared/types'
+
+const logger = getLogger('VoiceModeService')
+
+// ============================================================
+// 내부 타입
+// ============================================================
+
+interface VoiceSession {
+  id: string
+  mode: VoiceMode
+  startedAt: number
+  recognitionState: RecognitionState
+  audioState: AudioState
+  audioBufferDurationMs: number
+  transcription: string
+  processedText: string | null
+  accidentalPress: boolean
+}
+
+interface VoiceAction {
+  type: 'press' | 'release' | 'escape'
+  timestamp: number
+  mode: VoiceMode
+  hotkeyId: string
+}
+
+interface VoiceModeEvents {
+  'session-started': (payload: { session: VoiceSession }) => void
+  'recognition-state-changed': (payload: {
+    previous: RecognitionState
+    current: RecognitionState
+  }) => void
+  'audio-state-changed': (payload: {
+    previous: AudioState
+    current: AudioState
+  }) => void
+  'transcription-update': (payload: { text: string; isFinal: boolean }) => void
+  'session-completed': (payload: { session: VoiceSession; finalText: string }) => void
+  'session-cancelled': (payload: {
+    session: VoiceSession
+    reason: 'user' | 'timeout' | 'too-short'
+  }) => void
+  'audio-level': (payload: { level: number }) => void
+  error: (payload: { error: D3ROError; session: VoiceSession | null }) => void
+}
+
+// ============================================================
+// 터미널 상태 헬퍼
+// ============================================================
+
+const TERMINAL_STATES = new Set<RecognitionState>([
+  RecognitionState.COMPLETED,
+  RecognitionState.CANCELLED,
+  RecognitionState.ERROR,
+  RecognitionState.DESTROYED
+])
+
+// ============================================================
+// VoiceModeService
+// ============================================================
+
+class VoiceModeService extends EventEmitter {
+  private _session: VoiceSession | null = null
+  private _recognitionState = RecognitionState.IDLE
+  private _audioState = AudioState.IDLE
+
+  // 이중 조건 플러시
+  private _sttReady = false
+  private _audioStarted = false
+  private _audioBuffer: Buffer[] = []
+  private _audioBufferBytes = 0
+
+  // 에러 가드
+  private _errorEmitted = false
+
+  // Action Queue (이벤트 직렬화)
+  private _actionQueue: VoiceAction[] = []
+  private _isProcessingQueue = false
+
+  // 리스너 해제용 참조
+  private _audioDataHandler: ((payload: { buffer: Buffer }) => void) | null = null
+  private _audioLevelHandler: ((payload: { level: number }) => void) | null = null
+  private _hotkeyPressHandler: ((payload: { config: HotkeyConfig; timestamp: number }) => void) | null = null
+  private _hotkeyReleaseHandler: ((payload: { config: HotkeyConfig; durationMs: number; timestamp: number }) => void) | null = null
+  private _doublePressHandler: ((payload: { config: HotkeyConfig }) => void) | null = null
+
+  private _disposed = false
+
+  get currentSession(): VoiceSession | null {
+    return this._session
+  }
+
+  get isActive(): boolean {
+    return this._session !== null && !this._isInTerminalState()
+  }
+
+  getState(): VoiceState {
+    return {
+      recognitionState: this._recognitionState,
+      audioState: this._audioState,
+      mode: configGet('defaultLLMAction') === 'translate' ? 'hands-free' : 'dictation',
+      sessionId: this._session?.id ?? null,
+      recordingStartedAt: this._session?.startedAt ?? null
+    }
+  }
+
+  // ── 초기화 ──────────────────────────────────────────────
+
+  /**
+   * HotkeyService 이벤트를 구독하여 핫키 → 세션 제어를 연결한다.
+   * bootstrap에서 호출한다.
+   */
+  connectHotkey(): void {
+    const hotkey = getHotkeyService()
+
+    this._hotkeyPressHandler = (payload) => {
+      const mode = this._resolveMode(payload.config)
+      this._enqueueAction({ type: 'press', timestamp: payload.timestamp, mode, hotkeyId: payload.config.id })
+    }
+
+    this._hotkeyReleaseHandler = (payload) => {
+      const mode = this._resolveMode(payload.config)
+      this._enqueueAction({ type: 'release', timestamp: payload.timestamp, mode, hotkeyId: payload.config.id })
+    }
+
+    this._doublePressHandler = (payload) => {
+      // 더블프레스 → hands-free 모드 토글
+      this._enqueueAction({ type: 'press', timestamp: Date.now(), mode: 'hands-free', hotkeyId: payload.config.id })
+    }
+
+    hotkey.on('hotkey-pressed', this._hotkeyPressHandler)
+    hotkey.on('hotkey-released', this._hotkeyReleaseHandler)
+    hotkey.on('double-press', this._doublePressHandler)
+
+    logger.info('Hotkey events connected')
+  }
+
+  // ── 세션 제어 ──────────────────────────────────────────
+
+  async startSession(mode: VoiceMode): Promise<void> {
+    if (this._disposed) return
+    if (this._session && !this._isInTerminalState()) {
+      logger.warn('Session already active, ignoring startSession')
+      return
+    }
+
+    // 세션 생성
+    this._session = {
+      id: randomUUID(),
+      mode,
+      startedAt: Date.now(),
+      recognitionState: RecognitionState.PREPARING,
+      audioState: AudioState.IDLE,
+      audioBufferDurationMs: 0,
+      transcription: '',
+      processedText: null,
+      accidentalPress: false
+    }
+
+    this._errorEmitted = false
+    this._sttReady = false
+    this._audioStarted = false
+    this._audioBuffer = []
+    this._audioBufferBytes = 0
+
+    this._setRecognitionState(RecognitionState.PREPARING)
+    this.emit('session-started', { session: this._session })
+    logger.info(`Session started: ${this._session.id} (mode: ${mode})`)
+
+    // 이중 조건 플러시: STT 초기화 + 오디오 캡처를 병렬 시작
+    const sttPromise = this._initSTT()
+    const audioPromise = this._startAudio()
+
+    // 둘 다 에러여도 개별 처리하므로 allSettled
+    await Promise.allSettled([sttPromise, audioPromise])
+  }
+
+  async stopSession(): Promise<void> {
+    if (!this._session || this._isInTerminalState()) return
+
+    const session = this._session
+    const duration = Date.now() - session.startedAt
+
+    // accidentalPress 체크 (700ms 미만)
+    if (duration < TIMING.MIN_AUDIO_DURATION) {
+      session.accidentalPress = true
+      logger.info(`Accidental press detected (${duration}ms < ${TIMING.MIN_AUDIO_DURATION}ms)`)
+      this._cancelSession('too-short')
+      return
+    }
+
+    // 오디오 캡처 중지
+    await this._stopAudio()
+
+    // 버퍼가 있으면 STT에 전달
+    if (this._audioBuffer.length > 0 && this._sttReady) {
+      await this._transcribe()
+    } else if (this._audioBuffer.length > 0 && !this._sttReady) {
+      // STT 아직 준비 안 됨 → tryFlushAll이 처리
+      logger.info('Waiting for STT to be ready before transcribing')
+      // 타임아웃 설정
+      setTimeout(() => {
+        if (this._session?.id === session.id && !this._isInTerminalState()) {
+          logger.warn('STT readiness timeout, cancelling session')
+          this._cancelSession('timeout')
+        }
+      }, TIMING.POST_RECORDING_WAIT_BUFFERED)
+    } else {
+      // 오디오 없음
+      logger.warn('No audio buffer, cancelling session')
+      this._cancelSession('too-short')
+    }
+  }
+
+  cancelSession(): void {
+    this._cancelSession('user')
+  }
+
+  // ── 상태 머신 ──────────────────────────────────────────
+
+  private _isInTerminalState(): boolean {
+    return TERMINAL_STATES.has(this._recognitionState)
+  }
+
+  private _setRecognitionState(state: RecognitionState): void {
+    if (this._recognitionState === state) return
+    if (this._isInTerminalState() && state !== RecognitionState.IDLE) return
+
+    const previous = this._recognitionState
+    this._recognitionState = state
+    if (this._session) {
+      this._session.recognitionState = state
+    }
+
+    this.emit('recognition-state-changed', { previous, current: state })
+    logger.debug(`RecognitionState: ${previous} → ${state}`)
+  }
+
+  private _setAudioState(state: AudioState): void {
+    if (this._audioState === state) return
+
+    const previous = this._audioState
+    this._audioState = state
+    if (this._session) {
+      this._session.audioState = state
+    }
+
+    this.emit('audio-state-changed', { previous, current: state })
+    logger.debug(`AudioState: ${previous} → ${state}`)
+  }
+
+  // ── STT 초기화 ─────────────────────────────────────────
+
+  private async _initSTT(): Promise<void> {
+    try {
+      this._setRecognitionState(RecognitionState.CONNECTING)
+      const stt = getLocalSTTService()
+      const modelId = configGet('sttModelId')
+
+      await stt.initialize(modelId)
+
+      if (this._isInTerminalState()) return
+
+      this._sttReady = true
+      this._setRecognitionState(RecognitionState.READY)
+      logger.info('STT ready')
+
+      this._tryFlushAll()
+    } catch (error) {
+      if (this._isInTerminalState()) return
+      this._handleError(
+        new D3ROError(
+          ErrorCode.STTModelLoadFailed,
+          `STT initialization failed: ${error instanceof Error ? error.message : String(error)}`
+        )
+      )
+    }
+  }
+
+  // ── 오디오 캡처 ────────────────────────────────────────
+
+  private async _startAudio(): Promise<void> {
+    try {
+      this._setAudioState(AudioState.INITIALIZING)
+      const audio = getAudioCaptureService()
+
+      // 오디오 데이터 수신
+      this._audioDataHandler = (payload) => {
+        if (this._isInTerminalState()) return
+        this._audioBuffer.push(payload.buffer)
+        this._audioBufferBytes += payload.buffer.length
+
+        // 버퍼 duration 업데이트 (16kHz, 16bit, mono)
+        const durationMs = (this._audioBufferBytes / 2 / 16000) * 1000
+        if (this._session) {
+          this._session.audioBufferDurationMs = durationMs
+        }
+
+        this._tryFlushAll()
+      }
+
+      this._audioLevelHandler = (payload) => {
+        this.emit('audio-level', { level: payload.level })
+      }
+
+      audio.on('audio-data', this._audioDataHandler)
+      audio.on('audio-level', this._audioLevelHandler)
+
+      await audio.start()
+
+      if (this._isInTerminalState()) return
+
+      this._audioStarted = true
+      this._setAudioState(AudioState.STREAMING)
+      logger.info('Audio capture started')
+
+      this._tryFlushAll()
+    } catch (error) {
+      if (this._isInTerminalState()) return
+      this._setAudioState(AudioState.STOPPED)
+      this._handleError(
+        new D3ROError(
+          ErrorCode.AudioCaptureStartFailed,
+          `Audio capture failed: ${error instanceof Error ? error.message : String(error)}`
+        )
+      )
+    }
+  }
+
+  private async _stopAudio(): Promise<void> {
+    this._setAudioState(AudioState.STOPPED)
+
+    const audio = getAudioCaptureService()
+    if (this._audioDataHandler) {
+      audio.off('audio-data', this._audioDataHandler)
+      this._audioDataHandler = null
+    }
+    if (this._audioLevelHandler) {
+      audio.off('audio-level', this._audioLevelHandler)
+      this._audioLevelHandler = null
+    }
+
+    try {
+      await audio.stop()
+    } catch (error) {
+      logger.warn(`Audio stop error: ${error instanceof Error ? error.message : String(error)}`)
+    }
+  }
+
+  // ── 이중 조건 플러시 ───────────────────────────────────
+
+  private _tryFlushAll(): void {
+    if (!this._sttReady || !this._audioStarted) return
+    if (this._audioBuffer.length === 0) return
+    if (this._isInTerminalState()) return
+
+    // 아직 녹음 중이면 flush 하지 않음 (stopSession에서 처리)
+    if (this._audioState === AudioState.STREAMING) return
+
+    this._transcribe()
+  }
+
+  // ── 전사 ───────────────────────────────────────────────
+
+  private async _transcribe(): Promise<void> {
+    if (this._audioBuffer.length === 0) return
+    if (this._isInTerminalState()) return
+
+    this._setRecognitionState(RecognitionState.RECOGNIZING)
+
+    const merged = Buffer.concat(this._audioBuffer)
+    this._audioBuffer = []
+    this._audioBufferBytes = 0
+
+    try {
+      const stt = getLocalSTTService()
+      const language = configGet('sttLanguage')
+
+      const result: TranscriptionResult = await stt.transcribe(merged, {
+        language: language === 'auto' ? undefined : language
+      })
+
+      if (this._isInTerminalState()) return
+
+      if (this._session) {
+        this._session.transcription = result.text
+      }
+
+      this.emit('transcription-update', { text: result.text, isFinal: true })
+
+      // Phase 2: LLM 후처리 없이 바로 완료
+      this._completeSession(result.text)
+    } catch (error) {
+      if (this._isInTerminalState()) return
+      this._handleError(
+        new D3ROError(
+          ErrorCode.STTTranscriptionFailed,
+          `Transcription failed: ${error instanceof Error ? error.message : String(error)}`
+        )
+      )
+    }
+  }
+
+  // ── 세션 완료/취소 ─────────────────────────────────────
+
+  private _completeSession(finalText: string): void {
+    if (!this._session) return
+
+    this._setRecognitionState(RecognitionState.COMPLETED)
+    this._setAudioState(AudioState.STOPPED)
+
+    const session = { ...this._session }
+    logger.info(`Session completed: "${finalText.substring(0, 50)}${finalText.length > 50 ? '...' : ''}"`)
+
+    this.emit('session-completed', { session, finalText })
+
+    // IDLE로 복귀
+    this._resetToIdle()
+  }
+
+  private _cancelSession(reason: 'user' | 'timeout' | 'too-short'): void {
+    if (!this._session) return
+
+    this._setRecognitionState(RecognitionState.CANCELLED)
+    this._setAudioState(AudioState.STOPPED)
+
+    const session = { ...this._session }
+    logger.info(`Session cancelled: ${reason}`)
+
+    // 오디오 정리
+    this._stopAudio()
+
+    this.emit('session-cancelled', { session, reason })
+
+    this._resetToIdle()
+  }
+
+  private _resetToIdle(): void {
+    this._session = null
+    this._audioBuffer = []
+    this._audioBufferBytes = 0
+    this._sttReady = false
+    this._audioStarted = false
+    this._errorEmitted = false
+
+    // 약간의 딜레이 후 IDLE로 전이 (UI 애니메이션용)
+    setTimeout(() => {
+      if (!this._session) {
+        this._setRecognitionState(RecognitionState.IDLE)
+        this._setAudioState(AudioState.IDLE)
+      }
+    }, 200)
+  }
+
+  // ── 에러 처리 ──────────────────────────────────────────
+
+  private _handleError(error: D3ROError): void {
+    if (this._errorEmitted) return
+    this._errorEmitted = true
+
+    logger.error(`VoiceMode error [${error.code}]: ${error.message}`)
+    this._setRecognitionState(RecognitionState.ERROR)
+
+    this._stopAudio()
+
+    this.emit('error', { error, session: this._session ? { ...this._session } : null })
+    this._resetToIdle()
+  }
+
+  // ── Action Queue (이벤트 직렬화) ───────────────────────
+
+  private _enqueueAction(action: VoiceAction): void {
+    this._actionQueue.push(action)
+    this._processQueue()
+  }
+
+  private async _processQueue(): Promise<void> {
+    if (this._isProcessingQueue) return
+    this._isProcessingQueue = true
+
+    try {
+      while (this._actionQueue.length > 0) {
+        const action = this._actionQueue.shift()!
+        await this._processAction(action)
+      }
+    } finally {
+      this._isProcessingQueue = false
+    }
+  }
+
+  private async _processAction(action: VoiceAction): Promise<void> {
+    try {
+      switch (action.type) {
+        case 'press':
+          await this._handlePress(action)
+          break
+        case 'release':
+          await this._handleRelease(action)
+          break
+        case 'escape':
+          this.cancelSession()
+          break
+      }
+    } catch (error) {
+      logger.error(`Action processing error: ${error instanceof Error ? error.message : String(error)}`)
+    }
+  }
+
+  private async _handlePress(action: VoiceAction): Promise<void> {
+    if (action.mode === 'dictation') {
+      // Dictation: hold-to-talk — press로 시작
+      if (!this.isActive) {
+        await this.startSession('dictation')
+      }
+    } else if (action.mode === 'hands-free') {
+      // HandsFree: toggle
+      if (this.isActive) {
+        await this.stopSession()
+      } else {
+        await this.startSession('hands-free')
+      }
+    }
+  }
+
+  private async _handleRelease(action: VoiceAction): Promise<void> {
+    if (action.mode === 'dictation' && this.isActive) {
+      // Dictation: hold-to-talk — release로 종료 (200ms 딜레이)
+      await new Promise<void>((resolve) => setTimeout(resolve, 200))
+      await this.stopSession()
+    }
+    // HandsFree: release 무시
+  }
+
+  // ── 유틸리티 ───────────────────────────────────────────
+
+  private _resolveMode(config: HotkeyConfig): VoiceMode {
+    if (config.id === 'voice-handsfree' || config.doublePressEnabled) {
+      return 'hands-free'
+    }
+    return 'dictation'
+  }
+
+  // ── 종료 ───────────────────────────────────────────────
+
+  dispose(): void {
+    this._disposed = true
+    this._actionQueue = []
+
+    // 진행 중 세션 취소
+    if (this._session && !this._isInTerminalState()) {
+      this._cancelSession('user')
+    }
+
+    // 핫키 리스너 해제
+    const hotkey = getHotkeyService()
+    if (this._hotkeyPressHandler) {
+      hotkey.off('hotkey-pressed', this._hotkeyPressHandler)
+    }
+    if (this._hotkeyReleaseHandler) {
+      hotkey.off('hotkey-released', this._hotkeyReleaseHandler)
+    }
+    if (this._doublePressHandler) {
+      hotkey.off('double-press', this._doublePressHandler)
+    }
+
+    // 오디오 리스너 해제
+    this._stopAudio()
+
+    this._setRecognitionState(RecognitionState.DESTROYED)
+    this.removeAllListeners()
+    logger.info('VoiceModeService disposed')
+  }
+
+  // ── EventEmitter 타입 오버라이드 ───────────────────────
+
+  override on<K extends keyof VoiceModeEvents>(
+    event: K,
+    listener: VoiceModeEvents[K]
+  ): this {
+    return super.on(event, listener)
+  }
+
+  override off<K extends keyof VoiceModeEvents>(
+    event: K,
+    listener: VoiceModeEvents[K]
+  ): this {
+    return super.off(event, listener)
+  }
+
+  override emit<K extends keyof VoiceModeEvents>(
+    event: K,
+    ...args: Parameters<VoiceModeEvents[K]>
+  ): boolean {
+    return super.emit(event, ...args)
+  }
+}
+
+// ── 싱글톤 ─────────────────────────────────────────────
+
+let instance: VoiceModeService | null = null
+
+export function getVoiceModeService(): VoiceModeService {
+  if (!instance) {
+    instance = new VoiceModeService()
+  }
+  return instance
+}

src/main/services/index.ts

@@ -0,0 +1,26 @@
+// src/main/services/index.ts — 서비스 레지스트리
+
+export { initLoggerService, getLogger } from './LoggerService'
+export {
+  initConfigService,
+  getConfigService,
+  configGet,
+  configSet,
+  configGetAll,
+  configReset,
+  onConfigChanged
+} from './ConfigService'
+export {
+  getLocalSTTService,
+  LocalSTTService,
+  STTState
+} from './LocalSTTService'
+export type {
+  TranscriptionResult,
+  TranscriptionSegment,
+  TranscribeOptions,
+  LocalSTTEvents
+} from './LocalSTTService'
+export { getHotkeyService } from './HotkeyService'
+export { getVoiceModeService } from './VoiceModeService'
+export { getAudioCaptureService } from './AudioCaptureService'

src/main/types/node-record-lpcm16.d.ts

@@ -0,0 +1,33 @@
+// Type declarations for node-record-lpcm16 (no @types package available)
+
+declare module 'node-record-lpcm16' {
+  import { ChildProcess } from 'child_process'
+  import { Readable } from 'stream'
+
+  interface RecordingOptions {
+    sampleRate?: number
+    channels?: number
+    compress?: boolean
+    threshold?: number
+    thresholdStart?: number | null
+    thresholdEnd?: number | null
+    silence?: string
+    recorder?: 'sox' | 'rec' | 'arecord'
+    endOnSilence?: boolean
+    audioType?: string
+    device?: string
+  }
+
+  interface Recording {
+    process: ChildProcess
+    stop(): void
+    pause(): void
+    resume(): void
+    isPaused(): boolean
+    stream(): Readable
+  }
+
+  function record(options?: RecordingOptions): Recording
+
+  export { record, Recording, RecordingOptions }
+}

src/main/windows/TrayManager.ts

@@ -0,0 +1,55 @@
+// src/main/windows/TrayManager.ts
+
+import { Tray, Menu, app, nativeImage } from 'electron'
+import { join } from 'path'
+import { getMainWindow } from './WindowManager'
+import { getLogger } from '../services/LoggerService'
+import { setIsQuitting } from '../lifecycle'
+
+const logger = getLogger('TrayManager')
+
+let tray: Tray | null = null
+
+export function createTray(): void {
+  // 16x16 빈 아이콘 생성 (리소스 아이콘이 없을 때 폴백)
+  const icon = nativeImage.createEmpty()
+  tray = new Tray(icon)
+
+  const contextMenu = Menu.buildFromTemplate([
+    {
+      label: '표시',
+      click: () => {
+        const mainWindow = getMainWindow()
+        if (mainWindow) {
+          mainWindow.show()
+          mainWindow.focus()
+        }
+      }
+    },
+    { type: 'separator' },
+    {
+      label: '종료',
+      click: () => {
+        setIsQuitting(true)
+        app.quit()
+      }
+    }
+  ])
+
+  tray.setToolTip('D3RO Voice')
+  tray.setContextMenu(contextMenu)
+
+  tray.on('double-click', () => {
+    const mainWindow = getMainWindow()
+    if (mainWindow) {
+      mainWindow.show()
+      mainWindow.focus()
+    }
+  })
+
+  logger.info('Tray created')
+}
+
+export function getTray(): Tray | null {
+  return tray
+}

src/main/windows/WindowManager.ts

@@ -0,0 +1,66 @@
+// src/main/windows/WindowManager.ts
+
+import { BrowserWindow, shell } from 'electron'
+import { join } from 'path'
+import { is } from '@electron-toolkit/utils'
+import { WINDOW_SIZE } from '@shared/constants'
+import { getLogger } from '../services/LoggerService'
+import { getIsQuitting, setIsQuitting } from '../lifecycle'
+import { configGet } from '../services/ConfigService'
+
+const logger = getLogger('WindowManager')
+
+let mainWindow: BrowserWindow | null = null
+
+export function getMainWindow(): BrowserWindow | null {
+  return mainWindow
+}
+
+export function createMainWindow(): BrowserWindow {
+  mainWindow = new BrowserWindow({
+    width: WINDOW_SIZE.MAIN.width,
+    height: WINDOW_SIZE.MAIN.height,
+    minWidth: 800,
+    minHeight: 600,
+    show: false,
+    autoHideMenuBar: true,
+    webPreferences: {
+      preload: join(__dirname, '../preload/index.js'),
+      sandbox: false,
+      contextIsolation: true,
+      nodeIntegration: false
+    }
+  })
+
+  mainWindow.on('ready-to-show', () => {
+    mainWindow?.show()
+    logger.info('Main window shown')
+  })
+
+  mainWindow.on('close', (event) => {
+    if (!getIsQuitting() && configGet('closeToTray')) {
+      event.preventDefault()
+      mainWindow?.hide()
+      logger.info('Main window hidden to tray')
+    }
+  })
+
+  mainWindow.on('closed', () => {
+    mainWindow = null
+  })
+
+  mainWindow.webContents.setWindowOpenHandler((details) => {
+    shell.openExternal(details.url)
+    return { action: 'deny' }
+  })
+
+  // 개발/프로덕션 URL 로드
+  if (is.dev && process.env['ELECTRON_RENDERER_URL']) {
+    mainWindow.loadURL(process.env['ELECTRON_RENDERER_URL'])
+  } else {
+    mainWindow.loadFile(join(__dirname, '../renderer/index.html'))
+  }
+
+  logger.info('Main window created')
+  return mainWindow
+}

src/preload/index.ts

@@ -0,0 +1,164 @@
+// src/preload/index.ts
+// contextBridge로 렌더러에 노출할 API 정의
+
+import { contextBridge, ipcRenderer } from 'electron'
+import { IPC_CHANNELS } from '@shared/ipc-channels'
+import type {
+  AudioDevice,
+  SetDeviceParams,
+  TestDeviceParams,
+  TestDeviceResult,
+  AudioDeviceChangedEvent,
+  AppConfig,
+  ConfigGetParams,
+  ConfigSetParams,
+  ConfigResetParams,
+  SetThemeParams,
+  SetLanguageParams,
+  ThemeMode,
+  ConfigChangedEvent,
+  VoiceState,
+  VoiceMode,
+  AudioLevelEvent,
+  VoiceStateChangedEvent,
+  TranscriptionDeltaEvent,
+  TranscriptionCompleteEvent,
+  VoiceErrorEvent,
+  StartRecordingParams,
+  StartRecordingResult,
+  StopRecordingParams,
+  StopRecordingResult,
+  CancelRecordingParams,
+  SetVoiceModeParams,
+  STTStatus,
+  STTModel,
+  SetSTTModelParams,
+  SetSTTLanguageParams,
+  STTStatusChangedEvent,
+  HotkeyBinding,
+  SetHotkeyParams,
+  SetEnabledParams,
+  HotkeyTriggeredEvent,
+  PermissionStatus
+} from '@shared/types'
+import type { IPCResult } from '@shared/errors'
+
+type Unsubscribe = () => void
+
+function invoke<TResult>(channel: string, ...args: unknown[]): Promise<IPCResult<TResult>> {
+  return ipcRenderer.invoke(channel, ...args)
+}
+
+function send(channel: string, ...args: unknown[]): void {
+  ipcRenderer.send(channel, ...args)
+}
+
+function on<T>(channel: string, callback: (data: T) => void): Unsubscribe {
+  const listener = (_event: Electron.IpcRendererEvent, data: T) => callback(data)
+  ipcRenderer.on(channel, listener)
+  return () => ipcRenderer.removeListener(channel, listener)
+}
+
+const electronAPI = {
+  // ── Audio ──────────────────────────────────────────────
+  audio: {
+    getDevices: () => invoke<AudioDevice[]>(IPC_CHANNELS.AUDIO.GET_DEVICES),
+    getSelectedDevice: () => invoke<string | null>(IPC_CHANNELS.AUDIO.GET_SELECTED_DEVICE),
+    setSelectedDevice: (params: SetDeviceParams) =>
+      invoke<void>(IPC_CHANNELS.AUDIO.SET_SELECTED_DEVICE, params),
+    testDevice: (params: TestDeviceParams) =>
+      invoke<TestDeviceResult>(IPC_CHANNELS.AUDIO.TEST_DEVICE, params),
+    onDeviceChanged: (cb: (e: AudioDeviceChangedEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.AUDIO.DEVICE_CHANGED, cb)
+  },
+
+  // ── Config ─────────────────────────────────────────────
+  config: {
+    get: (params: ConfigGetParams) => invoke<unknown>(IPC_CHANNELS.CONFIG.GET, params),
+    set: (params: ConfigSetParams) => invoke<void>(IPC_CHANNELS.CONFIG.SET, params),
+    getAll: () => invoke<AppConfig>(IPC_CHANNELS.CONFIG.GET_ALL),
+    reset: (params: ConfigResetParams) => invoke<void>(IPC_CHANNELS.CONFIG.RESET, params),
+    getTheme: () => invoke<ThemeMode>(IPC_CHANNELS.CONFIG.GET_THEME),
+    setTheme: (params: SetThemeParams) => invoke<void>(IPC_CHANNELS.CONFIG.SET_THEME, params),
+    getLanguage: () => invoke<string>(IPC_CHANNELS.CONFIG.GET_LANGUAGE),
+    setLanguage: (params: SetLanguageParams) =>
+      invoke<void>(IPC_CHANNELS.CONFIG.SET_LANGUAGE, params),
+    onChanged: (cb: (e: ConfigChangedEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.CONFIG.CHANGED, cb)
+  },
+
+  // ── Voice ──────────────────────────────────────────────
+  voice: {
+    startRecording: (params: StartRecordingParams) =>
+      invoke<StartRecordingResult>(IPC_CHANNELS.VOICE.START_RECORDING, params),
+    stopRecording: (params: StopRecordingParams) =>
+      invoke<StopRecordingResult>(IPC_CHANNELS.VOICE.STOP_RECORDING, params),
+    cancelRecording: (params: CancelRecordingParams) =>
+      invoke<void>(IPC_CHANNELS.VOICE.CANCEL_RECORDING, params),
+    getState: () => invoke<VoiceState>(IPC_CHANNELS.VOICE.GET_STATE),
+    setMode: (params: SetVoiceModeParams) =>
+      invoke<void>(IPC_CHANNELS.VOICE.SET_MODE, params),
+    getMode: () => invoke<VoiceMode>(IPC_CHANNELS.VOICE.GET_MODE),
+    onStateChanged: (cb: (e: VoiceStateChangedEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.VOICE.STATE_CHANGED, cb),
+    onTranscriptionDelta: (cb: (e: TranscriptionDeltaEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.VOICE.TRANSCRIPTION_DELTA, cb),
+    onTranscriptionComplete: (cb: (e: TranscriptionCompleteEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.VOICE.TRANSCRIPTION_COMPLETE, cb),
+    onError: (cb: (e: VoiceErrorEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.VOICE.ERROR, cb),
+    onAudioLevel: (cb: (e: AudioLevelEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.VOICE.AUDIO_LEVEL, cb)
+  },
+
+  // ── STT ────────────────────────────────────────────────
+  stt: {
+    getStatus: () => invoke<STTStatus>(IPC_CHANNELS.STT.GET_STATUS),
+    getModels: () => invoke<STTModel[]>(IPC_CHANNELS.STT.GET_MODELS),
+    getActiveModel: () => invoke<string | null>(IPC_CHANNELS.STT.GET_ACTIVE_MODEL),
+    setModel: (params: SetSTTModelParams) =>
+      invoke<void>(IPC_CHANNELS.STT.SET_MODEL, params),
+    getLanguage: () => invoke<string>(IPC_CHANNELS.STT.GET_LANGUAGE),
+    setLanguage: (params: SetSTTLanguageParams) =>
+      invoke<void>(IPC_CHANNELS.STT.SET_LANGUAGE, params),
+    onStatusChanged: (cb: (e: STTStatusChangedEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.STT.STATUS_CHANGED, cb)
+  },
+
+  // ── Hotkey ─────────────────────────────────────────────
+  hotkey: {
+    getDictationShortcut: () =>
+      invoke<HotkeyBinding>(IPC_CHANNELS.HOTKEY.GET_DICTATION_SHORTCUT),
+    setDictationShortcut: (params: SetHotkeyParams) =>
+      invoke<void>(IPC_CHANNELS.HOTKEY.SET_DICTATION_SHORTCUT, params),
+    getHandsFreeShortcut: () =>
+      invoke<HotkeyBinding>(IPC_CHANNELS.HOTKEY.GET_HANDS_FREE_SHORTCUT),
+    setHandsFreeShortcut: (params: SetHotkeyParams) =>
+      invoke<void>(IPC_CHANNELS.HOTKEY.SET_HANDS_FREE_SHORTCUT, params),
+    isEnabled: () => invoke<boolean>(IPC_CHANNELS.HOTKEY.IS_ENABLED),
+    setEnabled: (params: SetEnabledParams) =>
+      invoke<void>(IPC_CHANNELS.HOTKEY.SET_ENABLED, params),
+    onTriggered: (cb: (e: HotkeyTriggeredEvent) => void): Unsubscribe =>
+      on(IPC_CHANNELS.HOTKEY.TRIGGERED, cb)
+  },
+
+  // ── Window ─────────────────────────────────────────────
+  window: {
+    minimize: () => send(IPC_CHANNELS.WINDOW.MINIMIZE),
+    maximize: () => send(IPC_CHANNELS.WINDOW.MAXIMIZE),
+    close: () => send(IPC_CHANNELS.WINDOW.CLOSE),
+    isMaximized: () => invoke<boolean>(IPC_CHANNELS.WINDOW.IS_MAXIMIZED)
+  },
+
+  // ── System ─────────────────────────────────────────────
+  system: {
+    getPlatform: () => invoke<NodeJS.Platform>(IPC_CHANNELS.SYSTEM.GET_PLATFORM),
+    getVersion: () => invoke<string>(IPC_CHANNELS.SYSTEM.GET_VERSION),
+    checkMicPermission: () =>
+      invoke<PermissionStatus>(IPC_CHANNELS.SYSTEM.CHECK_MIC_PERMISSION)
+  }
+} as const
+
+contextBridge.exposeInMainWorld('electronAPI', electronAPI)
+
+export type ElectronAPI = typeof electronAPI

src/renderer/App.tsx

@@ -0,0 +1,26 @@
+// src/renderer/App.tsx — 루트 컴포넌트
+
+import { useState, useMemo } from 'react'
+import { ThemeProvider, CssBaseline, useMediaQuery } from '@mui/material'
+import { lightTheme, darkTheme } from './theme'
+import { AppLayout } from './components/AppLayout'
+import type { ThemeMode } from '@shared/types'
+
+export function App(): React.ReactElement {
+  const [themeMode] = useState<ThemeMode>('auto')
+  const prefersDark = useMediaQuery('(prefers-color-scheme: dark)')
+
+  const theme = useMemo(() => {
+    if (themeMode === 'auto') {
+      return prefersDark ? darkTheme : lightTheme
+    }
+    return themeMode === 'dark' ? darkTheme : lightTheme
+  }, [themeMode, prefersDark])
+
+  return (
+    <ThemeProvider theme={theme}>
+      <CssBaseline />
+      <AppLayout />
+    </ThemeProvider>
+  )
+}

src/renderer/components/AppLayout.tsx

@@ -0,0 +1,110 @@
+// src/renderer/components/AppLayout.tsx
+
+import { useState } from 'react'
+import {
+  Box,
+  Drawer,
+  List,
+  ListItemButton,
+  ListItemIcon,
+  ListItemText,
+  Divider,
+  Typography,
+  Chip
+} from '@mui/material'
+import DashboardIcon from '@mui/icons-material/Dashboard'
+import HistoryIcon from '@mui/icons-material/History'
+import MenuBookIcon from '@mui/icons-material/MenuBook'
+import SettingsIcon from '@mui/icons-material/Settings'
+import { DashboardPage } from '../pages/DashboardPage'
+
+type Route = 'dashboard' | 'history' | 'dictionary'
+
+const DRAWER_WIDTH = 240
+
+const NAV_ITEMS: Array<{ route: Route; label: string; icon: React.ReactElement }> = [
+  { route: 'dashboard', label: 'Dashboard', icon: <DashboardIcon /> },
+  { route: 'history', label: 'History', icon: <HistoryIcon /> },
+  { route: 'dictionary', label: 'Dictionary', icon: <MenuBookIcon /> }
+]
+
+export function AppLayout(): React.ReactElement {
+  const [currentRoute, setCurrentRoute] = useState<Route>('dashboard')
+
+  return (
+    <Box sx={{ display: 'flex', height: '100vh' }}>
+      {/* Sidebar Drawer */}
+      <Drawer
+        variant="permanent"
+        sx={{
+          width: DRAWER_WIDTH,
+          flexShrink: 0,
+          '& .MuiDrawer-paper': {
+            width: DRAWER_WIDTH,
+            boxSizing: 'border-box'
+          }
+        }}
+      >
+        {/* Header */}
+        <Box sx={{ p: 2, display: 'flex', alignItems: 'center', gap: 1 }}>
+          <Typography variant="h6" noWrap sx={{ fontWeight: 700 }}>
+            D3RO Voice
+          </Typography>
+          <Chip label="v1.0" size="small" variant="outlined" />
+        </Box>
+
+        <Divider />
+
+        {/* Navigation */}
+        <List sx={{ flex: 1, pt: 1 }}>
+          {NAV_ITEMS.map((item) => (
+            <ListItemButton
+              key={item.route}
+              selected={currentRoute === item.route}
+              onClick={() => setCurrentRoute(item.route)}
+              sx={{ my: 0.5 }}
+            >
+              <ListItemIcon sx={{ minWidth: 40 }}>{item.icon}</ListItemIcon>
+              <ListItemText primary={item.label} />
+            </ListItemButton>
+          ))}
+        </List>
+
+        <Divider />
+
+        {/* Bottom */}
+        <List>
+          <ListItemButton sx={{ my: 0.5 }}>
+            <ListItemIcon sx={{ minWidth: 40 }}>
+              <SettingsIcon />
+            </ListItemIcon>
+            <ListItemText primary="Settings" />
+          </ListItemButton>
+        </List>
+      </Drawer>
+
+      {/* Content Area */}
+      <Box
+        component="main"
+        sx={{
+          flexGrow: 1,
+          p: 3,
+          overflow: 'auto',
+          bgcolor: 'background.default'
+        }}
+      >
+        {currentRoute === 'dashboard' && <DashboardPage />}
+        {currentRoute === 'history' && (
+          <Typography variant="h5" color="text.secondary">
+            History (Phase 5)
+          </Typography>
+        )}
+        {currentRoute === 'dictionary' && (
+          <Typography variant="h5" color="text.secondary">
+            Dictionary (Phase 5)
+          </Typography>
+        )}
+      </Box>
+    </Box>
+  )
+}

src/renderer/electron.d.ts

@@ -0,0 +1,8 @@
+// src/renderer/electron.d.ts
+import type { ElectronAPI } from '../preload/index'
+
+declare global {
+  interface Window {
+    electronAPI: ElectronAPI
+  }
+}

src/renderer/index.html

@@ -0,0 +1,12 @@
+<!doctype html>
+<html lang="ko">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>D3RO Voice</title>
+  </head>
+  <body>
+    <div id="root"></div>
+    <script type="module" src="./main.tsx"></script>
+  </body>
+</html>

src/renderer/main.tsx

@@ -0,0 +1,14 @@
+// src/renderer/main.tsx — 렌더러 진입점
+
+import { StrictMode } from 'react'
+import { createRoot } from 'react-dom/client'
+import { App } from './App'
+
+const root = document.getElementById('root')
+if (root) {
+  createRoot(root).render(
+    <StrictMode>
+      <App />
+    </StrictMode>
+  )
+}

src/renderer/pages/DashboardPage.tsx

@@ -0,0 +1,67 @@
+// src/renderer/pages/DashboardPage.tsx
+
+import { Box, Card, CardContent, Typography, Grid } from '@mui/material'
+import MicIcon from '@mui/icons-material/Mic'
+import TimerIcon from '@mui/icons-material/Timer'
+import TextFieldsIcon from '@mui/icons-material/TextFields'
+import TodayIcon from '@mui/icons-material/Today'
+
+interface StatCardProps {
+  title: string
+  value: string
+  icon: React.ReactElement
+}
+
+function StatCard({ title, value, icon }: StatCardProps): React.ReactElement {
+  return (
+    <Card>
+      <CardContent>
+        <Box sx={{ display: 'flex', alignItems: 'center', gap: 1, mb: 1 }}>
+          <Box sx={{ color: 'primary.main' }}>{icon}</Box>
+          <Typography variant="body2" color="text.secondary">
+            {title}
+          </Typography>
+        </Box>
+        <Typography variant="h4">{value}</Typography>
+      </CardContent>
+    </Card>
+  )
+}
+
+export function DashboardPage(): React.ReactElement {
+  return (
+    <Box>
+      <Typography variant="h5" sx={{ mb: 3, fontWeight: 600 }}>
+        Dashboard
+      </Typography>
+
+      <Grid container spacing={2}>
+        <Grid size={{ xs: 12, sm: 6, md: 3 }}>
+          <StatCard title="Total Sessions" value="0" icon={<MicIcon />} />
+        </Grid>
+        <Grid size={{ xs: 12, sm: 6, md: 3 }}>
+          <StatCard title="Total Time" value="0:00" icon={<TimerIcon />} />
+        </Grid>
+        <Grid size={{ xs: 12, sm: 6, md: 3 }}>
+          <StatCard title="Total Words" value="0" icon={<TextFieldsIcon />} />
+        </Grid>
+        <Grid size={{ xs: 12, sm: 6, md: 3 }}>
+          <StatCard title="Streak" value="0 days" icon={<TodayIcon />} />
+        </Grid>
+      </Grid>
+
+      <Box sx={{ mt: 4 }}>
+        <Typography variant="h6" sx={{ mb: 2 }}>
+          Recent Sessions
+        </Typography>
+        <Card>
+          <CardContent>
+            <Typography variant="body2" color="text.secondary" sx={{ textAlign: 'center', py: 4 }}>
+              No sessions yet. Press the hotkey to start recording.
+            </Typography>
+          </CardContent>
+        </Card>
+      </Box>
+    </Box>
+  )
+}

src/renderer/theme.ts

@@ -0,0 +1,148 @@
+// src/renderer/theme.ts — MUI 7 테마 정의 (설계서 03 기반)
+
+import { createTheme, type ThemeOptions } from '@mui/material/styles'
+
+const commonOptions: ThemeOptions = {
+  typography: {
+    fontFamily: [
+      '-apple-system',
+      'BlinkMacSystemFont',
+      '"Segoe UI"',
+      'Roboto',
+      '"Helvetica Neue"',
+      'Arial',
+      'sans-serif'
+    ].join(','),
+    h4: { fontWeight: 600, fontSize: '1.5rem' },
+    h5: { fontWeight: 600, fontSize: '1.25rem' },
+    h6: { fontWeight: 600, fontSize: '1rem' },
+    subtitle1: { fontWeight: 500 },
+    body1: { fontSize: '0.9375rem' },
+    body2: { fontSize: '0.8125rem' },
+    button: { textTransform: 'none' as const, fontWeight: 500 }
+  },
+  shape: {
+    borderRadius: 12
+  },
+  components: {
+    MuiButton: {
+      defaultProps: {
+        disableElevation: true
+      },
+      styleOverrides: {
+        root: {
+          textTransform: 'none',
+          fontWeight: 500,
+          borderRadius: 8,
+          padding: '8px 16px'
+        }
+      }
+    },
+    MuiCard: {
+      defaultProps: {
+        elevation: 0
+      },
+      styleOverrides: {
+        root: {
+          borderRadius: 12,
+          border: '1px solid'
+        }
+      }
+    },
+    MuiDrawer: {
+      styleOverrides: {
+        paper: {
+          width: 240,
+          borderRight: 'none'
+        }
+      }
+    },
+    MuiListItemButton: {
+      styleOverrides: {
+        root: {
+          borderRadius: 8,
+          marginLeft: 8,
+          marginRight: 8
+        }
+      }
+    },
+    MuiTextField: {
+      defaultProps: {
+        size: 'small',
+        variant: 'outlined'
+      }
+    },
+    MuiChip: {
+      styleOverrides: {
+        root: {
+          borderRadius: 6,
+          fontWeight: 500
+        }
+      }
+    }
+  }
+}
+
+export const lightTheme = createTheme({
+  ...commonOptions,
+  palette: {
+    mode: 'light',
+    primary: {
+      main: 'rgb(31, 93, 242)',
+      light: 'rgb(71, 133, 255)',
+      dark: 'rgb(20, 65, 180)',
+      contrastText: '#FFFFFF'
+    },
+    secondary: {
+      main: 'rgb(108, 117, 125)',
+      light: 'rgb(173, 181, 189)',
+      dark: 'rgb(73, 80, 87)'
+    },
+    background: {
+      default: '#F9F9F9',
+      paper: '#FFFFFF'
+    },
+    text: {
+      primary: 'rgba(0, 0, 0, 0.87)',
+      secondary: 'rgba(0, 0, 0, 0.6)'
+    },
+    divider: 'rgba(0, 0, 0, 0.08)',
+    error: { main: '#D32F2F' },
+    success: { main: '#2E7D32' },
+    warning: { main: '#ED6C02' }
+  }
+})
+
+export const darkTheme = createTheme({
+  ...commonOptions,
+  palette: {
+    mode: 'dark',
+    primary: {
+      main: 'rgb(71, 133, 255)',
+      light: 'rgb(120, 170, 255)',
+      dark: 'rgb(31, 93, 242)',
+      contrastText: '#FFFFFF'
+    },
+    secondary: {
+      main: 'rgb(173, 181, 189)',
+      light: 'rgb(206, 212, 218)',
+      dark: 'rgb(108, 117, 125)'
+    },
+    background: {
+      default: '#121212',
+      paper: '#1E1E1E'
+    },
+    text: {
+      primary: 'rgba(255, 255, 255, 0.87)',
+      secondary: 'rgba(255, 255, 255, 0.6)'
+    },
+    divider: 'rgba(255, 255, 255, 0.08)',
+    error: { main: '#EF5350' },
+    success: { main: '#4CAF50' },
+    warning: { main: '#FFA726' }
+  }
+})
+
+export function getTheme(mode: 'light' | 'dark') {
+  return mode === 'dark' ? darkTheme : lightTheme
+}

src/shared/constants.ts

@@ -0,0 +1,58 @@
+// src/shared/constants.ts
+
+/** 타이밍 상수 (Speakly 리버스엔지니어링 기반) */
+export const TIMING = {
+  /** 더블프레스 감지 간격 (ms) */
+  DOUBLE_PRESS_DURATION: 300,
+
+  /** 최소 녹음 시간 (ms) — 이하 자동 취소 */
+  MIN_AUDIO_DURATION: 700,
+
+  /** 녹음 후 STT 대기 시간 (ms) */
+  POST_RECORDING_WAIT: 4000,
+
+  /** 녹음 후 STT 대기 (버퍼 있을 때) (ms) */
+  POST_RECORDING_WAIT_BUFFERED: 6000,
+
+  /** STT 아이들 타임아웃 (ms) */
+  STT_IDLE_TIMEOUT: 30000,
+
+  /** 절대 최대 대기 시간 (ms) */
+  ABSOLUTE_MAX_WAIT: 120000,
+
+  /** 오디오 레벨 전송 간격 (ms) */
+  AUDIO_LEVEL_INTERVAL: 100,
+
+  /** 서비스 종료 타임아웃 (ms) */
+  SERVICE_DESTROY_TIMEOUT: 3000,
+
+  /** 사이드카 헬스체크 지연 (ms) */
+  SIDECAR_HEALTH_DELAY: 3000,
+
+  /** LLM 요청 타임아웃 (ms) */
+  LLM_REQUEST_TIMEOUT: 30000
+} as const
+
+/** 웨이브 바 상수 (RecordingTip) */
+export const WAVE_BAR = {
+  COUNT: 9,
+  ANIMATION_INTERVAL: 100,
+
+  /** 코사인 분포 가중치 (Speakly 패턴) */
+  COS_WEIGHTS: Array.from({ length: 9 }, (_, i) => Math.cos((i - 4) * (Math.PI / 9)))
+} as const
+
+/** 오디오 포맷 */
+export const AUDIO_FORMAT = {
+  SAMPLE_RATE: 16000,
+  CHANNELS: 1,
+  BIT_DEPTH: 16,
+  BYTES_PER_SAMPLE: 2
+} as const
+
+/** 윈도우 크기 */
+export const WINDOW_SIZE = {
+  MAIN: { width: 1104, height: 816 },
+  RECORDING_TIP: { width: 280, height: 80 },
+  RESULT_POPUP: { width: 400, height: 200 }
+} as const

src/shared/errors.ts

@@ -0,0 +1,162 @@
+// src/shared/errors.ts
+
+export enum ErrorCode {
+  // === Success ===
+  Success = 0,
+
+  // === STT (100-199) ===
+  STTEngineNotInstalled = 100,
+  STTModelNotFound = 101,
+  STTModelNotLoaded = 102,
+  STTModelLoadFailed = 103,
+  STTModelDownloadFailed = 104,
+  STTModelDownloadCancelled = 105,
+  STTTranscriptionFailed = 110,
+  STTTranscriptionTimeout = 111,
+  STTTranscriptionCancelled = 112,
+  STTNoAudioData = 113,
+  STTAudioTooShort = 114,
+  STTLanguageNotSupported = 120,
+  STTSidecarSpawnFailed = 130,
+  STTSidecarCrashed = 131,
+  STTSidecarCommunicationFailed = 132,
+  STTGPUNotAvailable = 140,
+
+  // === TTS (200-299) ===
+  TTSEngineNotInstalled = 200,
+  TTSVoiceNotFound = 201,
+  TTSVoiceNotLoaded = 202,
+  TTSVoiceLoadFailed = 203,
+  TTSVoiceDownloadFailed = 204,
+  TTSSynthesisFailed = 210,
+  TTSPlaybackFailed = 211,
+  TTSPlaybackInterrupted = 212,
+  TTSTextTooLong = 220,
+  TTSTextEmpty = 221,
+
+  // === LLM / Ollama (300-399) ===
+  LLMServerUnreachable = 300,
+  LLMServerConnectionFailed = 301,
+  LLMServerTimeout = 302,
+  LLMModelNotFound = 310,
+  LLMModelNotLoaded = 311,
+  LLMModelLoadFailed = 312,
+  LLMModelPullFailed = 313,
+  LLMModelPullCancelled = 314,
+  LLMProcessingFailed = 320,
+  LLMProcessingTimeout = 321,
+  LLMProcessingCancelled = 322,
+  LLMResponseParseFailed = 323,
+  LLMInvalidAction = 330,
+  LLMPromptTooLong = 331,
+
+  // === Audio (400-499) ===
+  AudioDeviceNotFound = 400,
+  AudioDeviceAccessDenied = 401,
+  AudioDeviceBusy = 402,
+  AudioCaptureStartFailed = 410,
+  AudioCaptureStopFailed = 411,
+  AudioCaptureFailed = 412,
+  AudioNoPermission = 420,
+  AudioStreamError = 430,
+  AudioBufferOverflow = 431,
+
+  // === Hotkey (500-599) ===
+  HotkeyRegistrationFailed = 500,
+  HotkeyConflict = 501,
+  HotkeySystemReserved = 502,
+  HotkeyHookInitFailed = 510,
+  HotkeyHookCrashed = 511,
+
+  // === TextInsert (600-699) ===
+  TextInsertFailed = 600,
+  TextInsertClipboardSaveFailed = 601,
+  TextInsertClipboardRestoreFailed = 602,
+  TextInsertKeySimulationFailed = 603,
+  TextInsertNoActiveWindow = 610,
+  TextInsertTargetAppNotResponding = 611,
+
+  // === History / Dictionary / DB (700-799) ===
+  DBOpenFailed = 700,
+  DBMigrationFailed = 701,
+  DBQueryFailed = 702,
+  DBWriteFailed = 703,
+  HistoryNotFound = 710,
+  HistoryExportFailed = 711,
+  DictionaryNotFound = 720,
+  DictionaryDuplicate = 721,
+  DictionaryImportFailed = 722,
+  DictionaryExportFailed = 723,
+  DictionaryImportInvalidFormat = 724,
+
+  // === Config (800-899) ===
+  ConfigReadFailed = 800,
+  ConfigWriteFailed = 801,
+  ConfigInvalidValue = 802,
+  ConfigKeyNotFound = 803,
+  ConfigResetFailed = 804,
+  ConfigMigrationFailed = 810,
+
+  // === System / Window (900-999) ===
+  WindowCreationFailed = 900,
+  WindowNotFound = 901,
+  TrayCreationFailed = 910,
+  NotificationFailed = 920,
+  PermissionDenied = 930,
+  ExternalOpenFailed = 940,
+  SoundPlayFailed = 950,
+  AppAlreadyRunning = 960,
+  UnknownError = 999
+}
+
+/**
+ * D3RO-VOICE 표준 에러 객체 (Speakly NXError 패턴)
+ */
+export class D3ROError extends Error {
+  readonly code: ErrorCode
+  readonly details?: Record<string, unknown>
+
+  constructor(code: ErrorCode, message: string, details?: Record<string, unknown>) {
+    super(message)
+    this.name = 'D3ROError'
+    this.code = code
+    this.details = details
+  }
+
+  toJSON(): D3ROErrorJSON {
+    return {
+      code: this.code,
+      message: this.message,
+      details: this.details
+    }
+  }
+
+  static fromJSON(json: D3ROErrorJSON): D3ROError {
+    return new D3ROError(json.code, json.message, json.details)
+  }
+}
+
+export interface D3ROErrorJSON {
+  code: ErrorCode
+  message: string
+  details?: Record<string, unknown>
+}
+
+/**
+ * IPC 핸들러에서 사용하는 표준 응답 래퍼.
+ */
+export type IPCResult<T> =
+  | { success: true; data: T }
+  | { success: false; error: D3ROErrorJSON }
+
+export function ipcSuccess<T>(data: T): IPCResult<T> {
+  return { success: true, data }
+}
+
+export function ipcError<T>(
+  code: ErrorCode,
+  message: string,
+  details?: Record<string, unknown>
+): IPCResult<T> {
+  return { success: false, error: { code, message, details } }
+}

src/shared/ipc-channels.ts

@@ -0,0 +1,172 @@
+// src/shared/ipc-channels.ts
+// IPC 채널명 중앙 정의 — 모든 채널명은 이 파일에서만 정의한다.
+
+export const IPC_CHANNELS = {
+  VOICE: {
+    START_RECORDING: 'voice:startRecording',
+    STOP_RECORDING: 'voice:stopRecording',
+    CANCEL_RECORDING: 'voice:cancelRecording',
+    GET_STATE: 'voice:getState',
+    SET_MODE: 'voice:setMode',
+    GET_MODE: 'voice:getMode',
+    // Main → Renderer events
+    STATE_CHANGED: 'voice:stateChanged',
+    TRANSCRIPTION_DELTA: 'voice:transcriptionDelta',
+    TRANSCRIPTION_COMPLETE: 'voice:transcriptionComplete',
+    ERROR: 'voice:error',
+    AUDIO_LEVEL: 'voice:audioLevel'
+  },
+
+  AUDIO: {
+    GET_DEVICES: 'audio:getDevices',
+    GET_SELECTED_DEVICE: 'audio:getSelectedDevice',
+    SET_SELECTED_DEVICE: 'audio:setSelectedDevice',
+    TEST_DEVICE: 'audio:testDevice',
+    // Main → Renderer events
+    DEVICE_CHANGED: 'audio:deviceChanged'
+  },
+
+  STT: {
+    GET_STATUS: 'stt:getStatus',
+    GET_MODELS: 'stt:getModels',
+    GET_ACTIVE_MODEL: 'stt:getActiveModel',
+    SET_MODEL: 'stt:setModel',
+    DOWNLOAD_MODEL: 'stt:downloadModel',
+    CANCEL_DOWNLOAD: 'stt:cancelDownload',
+    GET_LANGUAGE: 'stt:getLanguage',
+    SET_LANGUAGE: 'stt:setLanguage',
+    // Main → Renderer events
+    STATUS_CHANGED: 'stt:statusChanged',
+    DOWNLOAD_PROGRESS: 'stt:downloadProgress'
+  },
+
+  TTS: {
+    SPEAK: 'tts:speak',
+    STOP: 'tts:stop',
+    GET_VOICES: 'tts:getVoices',
+    GET_ACTIVE_VOICE: 'tts:getActiveVoice',
+    SET_VOICE: 'tts:setVoice',
+    GET_STATUS: 'tts:getStatus',
+    DOWNLOAD_VOICE: 'tts:downloadVoice',
+    // Main → Renderer events
+    STATUS_CHANGED: 'tts:statusChanged',
+    SPEAKING_STATE_CHANGED: 'tts:speakingStateChanged'
+  },
+
+  LLM: {
+    GET_STATUS: 'llm:getStatus',
+    GET_MODELS: 'llm:getModels',
+    GET_ACTIVE_MODEL: 'llm:getActiveModel',
+    SET_MODEL: 'llm:setModel',
+    PROCESS: 'llm:process',
+    CANCEL_PROCESS: 'llm:cancelProcess',
+    GET_SERVER_URL: 'llm:getServerUrl',
+    SET_SERVER_URL: 'llm:setServerUrl',
+    PULL_MODEL: 'llm:pullModel',
+    // Main → Renderer events
+    STATUS_CHANGED: 'llm:statusChanged',
+    PROCESS_PROGRESS: 'llm:processProgress',
+    PULL_PROGRESS: 'llm:pullProgress'
+  },
+
+  HOTKEY: {
+    GET_DICTATION_SHORTCUT: 'hotkey:getDictationShortcut',
+    SET_DICTATION_SHORTCUT: 'hotkey:setDictationShortcut',
+    GET_HANDS_FREE_SHORTCUT: 'hotkey:getHandsFreeShortcut',
+    SET_HANDS_FREE_SHORTCUT: 'hotkey:setHandsFreeShortcut',
+    GET_COMMAND_SHORTCUT: 'hotkey:getCommandShortcut',
+    SET_COMMAND_SHORTCUT: 'hotkey:setCommandShortcut',
+    IS_ENABLED: 'hotkey:isEnabled',
+    SET_ENABLED: 'hotkey:setEnabled',
+    START_RECORDING: 'hotkey:startRecording',
+    STOP_RECORDING: 'hotkey:stopRecording',
+    // Main → Renderer events
+    TRIGGERED: 'hotkey:triggered',
+    RECORDING_RESULT: 'hotkey:recordingResult'
+  },
+
+  CONFIG: {
+    GET: 'config:get',
+    SET: 'config:set',
+    GET_ALL: 'config:getAll',
+    RESET: 'config:reset',
+    GET_THEME: 'config:getTheme',
+    SET_THEME: 'config:setTheme',
+    GET_LANGUAGE: 'config:getLanguage',
+    SET_LANGUAGE: 'config:setLanguage',
+    GET_AUTO_LAUNCH: 'config:getAutoLaunch',
+    SET_AUTO_LAUNCH: 'config:setAutoLaunch',
+    GET_CLOSE_TO_TRAY: 'config:getCloseToTray',
+    SET_CLOSE_TO_TRAY: 'config:setCloseToTray',
+    // Main → Renderer events
+    CHANGED: 'config:changed'
+  },
+
+  HISTORY: {
+    GET_ALL: 'history:getAll',
+    GET_BY_ID: 'history:getById',
+    DELETE: 'history:delete',
+    DELETE_ALL: 'history:deleteAll',
+    SEARCH: 'history:search',
+    EXPORT: 'history:export',
+    // Main → Renderer events
+    ADDED: 'history:added'
+  },
+
+  DICTIONARY: {
+    GET_ALL: 'dictionary:getAll',
+    ADD: 'dictionary:add',
+    UPDATE: 'dictionary:update',
+    DELETE: 'dictionary:delete',
+    IMPORT: 'dictionary:import',
+    EXPORT: 'dictionary:export',
+    SEARCH: 'dictionary:search'
+  },
+
+  WINDOW: {
+    MINIMIZE: 'window:minimize',
+    MAXIMIZE: 'window:maximize',
+    CLOSE: 'window:close',
+    IS_MAXIMIZED: 'window:isMaximized',
+    SHOW_RECORDING_TIP: 'window:showRecordingTip',
+    HIDE_RECORDING_TIP: 'window:hideRecordingTip',
+    SHOW_RESULT_POPUP: 'window:showResultPopup',
+    HIDE_RESULT_POPUP: 'window:hideResultPopup',
+    TIP_MEASURED: 'window:tipMeasured',
+    // Main → Renderer events
+    TIP_STATE_CHANGED: 'window:tipStateChanged',
+    TIP_PREPARE: 'window:tipPrepare',
+    TIP_SHOW: 'window:tipShow'
+  },
+
+  SYSTEM: {
+    GET_PLATFORM: 'system:getPlatform',
+    GET_VERSION: 'system:getVersion',
+    CHECK_MIC_PERMISSION: 'system:checkMicPermission',
+    REQUEST_MIC_PERMISSION: 'system:requestMicPermission',
+    SHOW_NOTIFICATION: 'system:showNotification',
+    OPEN_EXTERNAL: 'system:openExternal',
+    GET_ACTIVE_APP: 'system:getActiveApp',
+    INSERT_TEXT: 'system:insertText',
+    PLAY_SOUND: 'system:playSound',
+    SET_SOUND_ENABLED: 'system:setSoundEnabled',
+    IS_SOUND_ENABLED: 'system:isSoundEnabled'
+  },
+
+  STATS: {
+    GET_SUMMARY: 'stats:getSummary',
+    GET_DAILY: 'stats:getDaily',
+    GET_WEEKLY: 'stats:getWeekly',
+    // Main → Renderer events
+    UPDATED: 'stats:updated'
+  }
+} as const
+
+// 타입 유틸리티: 채널명 유니온 추출
+type NestedValues<T> = T extends Record<string, infer V>
+  ? V extends string
+    ? V
+    : NestedValues<V>
+  : never
+
+export type IPCChannel = NestedValues<typeof IPC_CHANNELS>

src/shared/types.ts

@@ -0,0 +1,658 @@
+// src/shared/types.ts
+// 모든 IPC 파라미터/반환 타입 정의
+
+// ============================================================
+// Common
+// ============================================================
+
+export type ThemeMode = 'light' | 'dark' | 'auto'
+
+export type VoiceMode = 'dictation' | 'hands-free'
+
+export type PermissionStatus = 'granted' | 'denied' | 'unknown'
+
+// ============================================================
+// Voice (음성 오케스트레이션)
+// ============================================================
+
+export enum RecognitionState {
+  IDLE = 'idle',
+  PREPARING = 'preparing',
+  CONNECTING = 'connecting',
+  READY = 'ready',
+  RECOGNIZING = 'recognizing',
+  COMPLETED = 'completed',
+  CANCELLED = 'cancelled',
+  ERROR = 'error',
+  DESTROYED = 'destroyed'
+}
+
+export enum AudioState {
+  IDLE = 'idle',
+  INITIALIZING = 'initializing',
+  STREAMING = 'streaming',
+  STOPPED = 'stopped'
+}
+
+export interface VoiceState {
+  recognitionState: RecognitionState
+  audioState: AudioState
+  mode: VoiceMode
+  sessionId: string | null
+  recordingStartedAt: number | null
+}
+
+export interface StartRecordingParams {
+  sessionId?: string
+  deviceId?: string
+}
+
+export interface StartRecordingResult {
+  sessionId: string
+}
+
+export interface StopRecordingParams {
+  sessionId: string
+}
+
+export interface StopRecordingResult {
+  sessionId: string
+  text: string
+  durationMs: number
+}
+
+export interface CancelRecordingParams {
+  sessionId: string
+}
+
+export interface SetVoiceModeParams {
+  mode: VoiceMode
+}
+
+// Voice events (Main → Renderer)
+
+export interface VoiceStateChangedEvent {
+  previousState: RecognitionState
+  currentState: RecognitionState
+  audioState: AudioState
+  sessionId: string | null
+}
+
+export interface TranscriptionDeltaEvent {
+  sessionId: string
+  text: string
+  delta: string
+  isFinal: boolean
+}
+
+export interface TranscriptionCompleteEvent {
+  sessionId: string
+  text: string
+  durationMs: number
+  language: string
+}
+
+export interface VoiceErrorEvent {
+  sessionId: string | null
+  errorCode: number
+  message: string
+}
+
+export interface AudioLevelEvent {
+  level: number
+}
+
+// ============================================================
+// Audio (디바이스 & 캡처)
+// ============================================================
+
+export interface AudioDevice {
+  deviceId: string
+  label: string
+  isDefault: boolean
+}
+
+export interface SetDeviceParams {
+  deviceId: string
+}
+
+export interface TestDeviceParams {
+  deviceId: string
+  durationMs?: number
+}
+
+export interface TestDeviceResult {
+  averageLevel: number
+  peakLevel: number
+  hasAudio: boolean
+}
+
+export interface AudioDeviceChangedEvent {
+  devices: AudioDevice[]
+  type: 'added' | 'removed' | 'default-changed'
+}
+
+// ============================================================
+// STT (로컬 Whisper)
+// ============================================================
+
+export enum STTEngineState {
+  NOT_INSTALLED = 'not-installed',
+  DOWNLOADING = 'downloading',
+  LOADING = 'loading',
+  READY = 'ready',
+  PROCESSING = 'processing',
+  ERROR = 'error'
+}
+
+export interface STTStatus {
+  engineState: STTEngineState
+  activeModel: string | null
+  engineVersion: string | null
+  gpuAccelerated: boolean
+}
+
+export interface STTModel {
+  id: string
+  name: string
+  sizeBytes: number
+  downloaded: boolean
+  languages: string[]
+  accuracy: number
+  speed: number
+}
+
+export interface SetSTTModelParams {
+  modelId: string
+}
+
+export interface DownloadModelParams {
+  modelId: string
+}
+
+export interface SetSTTLanguageParams {
+  language: string
+}
+
+export interface STTStatusChangedEvent {
+  status: STTStatus
+}
+
+export interface DownloadProgressEvent {
+  modelId: string
+  percent: number
+  downloadedBytes: number
+  totalBytes: number
+  bytesPerSecond: number
+}
+
+// ============================================================
+// TTS (로컬 TTS)
+// ============================================================
+
+export enum TTSEngineState {
+  NOT_INSTALLED = 'not-installed',
+  LOADING = 'loading',
+  READY = 'ready',
+  SPEAKING = 'speaking',
+  ERROR = 'error'
+}
+
+export interface TTSStatus {
+  engineState: TTSEngineState
+  activeVoice: string | null
+  engineVersion: string | null
+}
+
+export interface TTSVoice {
+  id: string
+  name: string
+  language: string
+  gender: 'male' | 'female' | 'neutral'
+  downloaded: boolean
+  sizeBytes: number
+}
+
+export interface TTSSpeakParams {
+  text: string
+  voiceId?: string
+  speed?: number
+}
+
+export interface TTSSpeakResult {
+  durationMs: number
+}
+
+export interface SetTTSVoiceParams {
+  voiceId: string
+}
+
+export interface DownloadVoiceParams {
+  voiceId: string
+}
+
+export interface TTSStatusChangedEvent {
+  status: TTSStatus
+}
+
+export interface SpeakingStateChangedEvent {
+  isSpeaking: boolean
+  text: string
+}
+
+// ============================================================
+// LLM (Ollama)
+// ============================================================
+
+export enum LLMConnectionState {
+  DISCONNECTED = 'disconnected',
+  CONNECTING = 'connecting',
+  CONNECTED = 'connected',
+  ERROR = 'error'
+}
+
+export interface LLMStatus {
+  connectionState: LLMConnectionState
+  serverUrl: string
+  activeModel: string | null
+  serverVersion: string | null
+}
+
+export interface LLMModel {
+  id: string
+  name: string
+  sizeBytes: number
+  parameterSize: string
+  quantization: string
+  modifiedAt: string
+}
+
+export type LLMAction = 'refine' | 'translate' | 'summarize' | 'expand' | 'grammar' | 'custom'
+
+export interface LLMProcessParams {
+  text: string
+  action: LLMAction
+  targetLanguage?: string
+  customPrompt?: string
+  modelId?: string
+}
+
+export interface LLMProcessResult {
+  originalText: string
+  processedText: string
+  action: LLMAction
+  processingTimeMs: number
+  tokenCount: number
+}
+
+export interface SetLLMModelParams {
+  modelId: string
+}
+
+export interface SetServerUrlParams {
+  url: string
+}
+
+export interface PullModelParams {
+  modelName: string
+}
+
+export interface LLMStatusChangedEvent {
+  status: LLMStatus
+}
+
+export interface LLMProcessProgressEvent {
+  text: string
+  token: string
+  done: boolean
+}
+
+export interface LLMPullProgressEvent {
+  modelName: string
+  status: string
+  percent: number
+  downloadedBytes: number
+  totalBytes: number
+}
+
+// ============================================================
+// Hotkey (핫키)
+// ============================================================
+
+export interface HotkeyBinding {
+  keyCode: number
+  ctrl: boolean
+  alt: boolean
+  shift: boolean
+  meta: boolean
+  displayLabel: string
+}
+
+export interface SetHotkeyParams {
+  binding: HotkeyBinding
+}
+
+export interface SetEnabledParams {
+  enabled: boolean
+}
+
+export type HotkeyAction = 'dictation' | 'hands-free' | 'command'
+
+export interface HotkeyTriggeredEvent {
+  action: HotkeyAction
+  type: 'pressed' | 'released'
+  isDoublePress: boolean
+}
+
+export interface HotkeyRecordingResultEvent {
+  binding: HotkeyBinding | null
+  conflictReason: string | null
+}
+
+// ============================================================
+// Config (설정)
+// ============================================================
+
+export interface AppConfig {
+  theme: ThemeMode
+  language: string
+  closeToTray: boolean
+  autoLaunch: boolean
+  soundEnabled: boolean
+  selectedDeviceId: string | null
+  sttModelId: string
+  sttLanguage: string
+  ttsVoiceId: string | null
+  ttsSpeed: number
+  ollamaServerUrl: string
+  llmModelId: string | null
+  defaultLLMAction: LLMAction
+  dictationShortcut: HotkeyBinding
+  handsFreeShortcut: HotkeyBinding
+  commandShortcut: HotkeyBinding
+  hotkeyEnabled: boolean
+  insertMethod: 'clipboard' | 'keyboard'
+  autoInsert: boolean
+  maxHistoryEntries: number
+}
+
+export interface ConfigGetParams {
+  key: keyof AppConfig
+}
+
+export interface ConfigSetParams {
+  key: keyof AppConfig
+  value: AppConfig[keyof AppConfig]
+}
+
+export interface ConfigResetParams {
+  key?: keyof AppConfig
+}
+
+export interface SetThemeParams {
+  theme: ThemeMode
+}
+
+export interface SetLanguageParams {
+  language: string
+}
+
+export interface SetAutoLaunchParams {
+  enabled: boolean
+}
+
+export interface SetCloseToTrayParams {
+  enabled: boolean
+}
+
+export interface ConfigChangedEvent {
+  key: keyof AppConfig
+  value: AppConfig[keyof AppConfig]
+  previousValue: AppConfig[keyof AppConfig]
+}
+
+// ============================================================
+// History (히스토리)
+// ============================================================
+
+export interface HistoryEntry {
+  id: string
+  originalText: string
+  polishedText: string | null
+  focusedApp: string | null
+  focusedAppName: string | null
+  focusedAppWindowTitle: string | null
+  mode: 'dictation' | 'translate' | 'command'
+  status: 'completed' | 'cancelled' | 'error'
+  errorCode: string | null
+  audioLocalPath: string | null
+  duration: number
+  detectedLanguage: string | null
+  micDevice: string | null
+  wordCount: number
+  sttModel: string | null
+  llmModel: string | null
+  sttLatencyMs: number | null
+  llmLatencyMs: number | null
+  createdAt: number
+  updatedAt: number
+  appVersion: string
+}
+
+export interface HistoryQueryParams {
+  page: number
+  pageSize: number
+  sortBy?: 'createdAt' | 'durationMs' | 'wordCount'
+  sortOrder?: 'asc' | 'desc'
+}
+
+export interface HistoryPage {
+  entries: HistoryEntry[]
+  total: number
+  page: number
+  pageSize: number
+  totalPages: number
+}
+
+export interface HistoryGetByIdParams {
+  id: string
+}
+
+export interface HistoryDeleteParams {
+  id: string
+}
+
+export interface HistorySearchParams {
+  query: string
+  page: number
+  pageSize: number
+}
+
+export interface HistoryExportParams {
+  format: 'json' | 'csv'
+  from?: string
+  to?: string
+}
+
+// ============================================================
+// Dictionary (사전)
+// ============================================================
+
+export interface DictionaryEntry {
+  id: string
+  word: string
+  pronunciation: string | null
+  category: 'user' | 'auto' | 'technical'
+  usageCount: number
+  lastUsedAt: number | null
+  createdAt: number
+  updatedAt: number
+}
+
+export interface DictionaryQueryParams {
+  page: number
+  pageSize: number
+  sortBy?: 'word' | 'category' | 'usageCount' | 'createdAt'
+  sortOrder?: 'asc' | 'desc'
+}
+
+export interface DictionaryPage {
+  entries: DictionaryEntry[]
+  total: number
+  page: number
+  pageSize: number
+  totalPages: number
+}
+
+export interface DictionaryAddParams {
+  word: string
+  pronunciation?: string
+  category?: 'user' | 'auto' | 'technical'
+}
+
+export interface DictionaryUpdateParams {
+  id: string
+  word?: string
+  pronunciation?: string
+  category?: 'user' | 'auto' | 'technical'
+}
+
+export interface DictionaryDeleteParams {
+  id: string
+}
+
+export interface DictionaryImportParams {
+  filePath: string
+  format: 'json' | 'csv'
+}
+
+export interface DictionaryImportResult {
+  imported: number
+  skipped: number
+  errors: number
+}
+
+export interface DictionaryExportParams {
+  format: 'json' | 'csv'
+}
+
+export interface DictionarySearchParams {
+  query: string
+  page: number
+  pageSize: number
+}
+
+// ============================================================
+// Window (윈도우 제어)
+// ============================================================
+
+export type RecordingTipState = 'opening' | 'recording' | 'thinking' | 'result' | 'error'
+
+export interface ShowRecordingTipParams {
+  state: RecordingTipState
+  text?: string
+  errorMessage?: string
+}
+
+export interface ShowResultPopupParams {
+  text: string
+  autoHideMs?: number
+}
+
+export interface TipMeasuredParams {
+  width: number
+  height: number
+}
+
+export interface TipStateChangedEvent {
+  state: RecordingTipState
+  text?: string
+  errorMessage?: string
+}
+
+export interface TipPrepareEvent {
+  state: RecordingTipState
+  text?: string
+}
+
+export interface TipShowEvent {
+  state: RecordingTipState
+}
+
+// ============================================================
+// System (시스템)
+// ============================================================
+
+export interface ActiveAppInfo {
+  name: string
+  title: string
+  pid: number
+}
+
+export interface ShowNotificationParams {
+  title: string
+  body: string
+  type?: 'info' | 'warning' | 'error'
+}
+
+export interface OpenExternalParams {
+  url: string
+}
+
+export interface InsertTextParams {
+  text: string
+  method?: 'clipboard' | 'keyboard'
+}
+
+export interface InsertTextResult {
+  success: boolean
+  insertedLength: number
+}
+
+export type SoundEffect =
+  | 'recording-start'
+  | 'recording-stop'
+  | 'transcription-complete'
+  | 'error'
+  | 'notification'
+
+export interface PlaySoundParams {
+  sound: SoundEffect
+}
+
+export interface SetSoundEnabledParams {
+  enabled: boolean
+}
+
+// ============================================================
+// Stats (통계)
+// ============================================================
+
+export interface StatsSummary {
+  totalRecordingTimeMs: number
+  totalWordCount: number
+  totalSessionCount: number
+  todayRecordingTimeMs: number
+  todayWordCount: number
+  todaySessionCount: number
+  streakDays: number
+}
+
+export interface StatsQueryParams {
+  from: string
+  to: string
+}
+
+export interface DailyStats {
+  date: string
+  recordingTimeMs: number
+  wordCount: number
+  sessionCount: number
+}
+
+export interface WeeklyStats {
+  weekStart: string
+  recordingTimeMs: number
+  wordCount: number
+  sessionCount: number
+}