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/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')
+  })
+}