오디오 소스 선택 기능 추가

- AudioCaptureService.getDevices(): PowerShell로 Windows 오디오 디바이스 열거
- SettingsModal 오디오 탭: 마이크 선택 드롭다운 (기본 + 감지된 디바이스)
- 선택 변경 시 ConfigService에 저장 → 다음 녹음 시 적용

src/main/services/AudioCaptureService.ts

@@ -227,15 +227,40 @@ class AudioCaptureService extends EventEmitter {
   }
 
   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
-      }
+    const devices: AudioDevice[] = [
+      { deviceId: 'default', label: '시스템 기본 마이크', isDefault: true },
     ]
+
+    try {
+      // PowerShell로 Windows 오디오 입력 디바이스 열거
+      const { execSync } = await import('child_process')
+      const psCommand = `Get-CimInstance Win32_SoundDevice | Where-Object { $_.StatusInfo -eq 3 } | Select-Object -Property DeviceID, Name | ConvertTo-Json -Compress`
+      const output = execSync(`powershell -NoProfile -Command "${psCommand}"`, {
+        encoding: 'utf8',
+        timeout: 5000,
+      }).trim()
+
+      if (output) {
+        const parsed: unknown = JSON.parse(output.startsWith('[') ? output : `[${output}]`)
+        if (Array.isArray(parsed)) {
+          for (const dev of parsed) {
+            const d = dev as { DeviceID?: string; Name?: string }
+            if (d.DeviceID && d.Name) {
+              devices.push({
+                deviceId: d.DeviceID,
+                label: d.Name,
+                isDefault: false,
+              })
+            }
+          }
+        }
+      }
+    } catch (err) {
+      logger.warn(`Failed to enumerate audio devices via PowerShell: ${err instanceof Error ? err.message : String(err)}`)
+    }
+
+    logger.debug(`Found ${devices.length} audio device(s)`)
+    return devices
   }
 
   getCurrentDevice(): AudioDevice | null {

src/renderer/components/SettingsModal.tsx

@@ -29,7 +29,8 @@ import KeyboardIcon from '@mui/icons-material/Keyboard'
 import EditIcon from '@mui/icons-material/Edit'
 import { d3roPalette } from '../theme'
 import { HotkeyRecordModal } from './HotkeyRecordModal'
-import type { ThemeMode, AppConfig, HotkeyBinding } from '@shared/types'
+import MicIcon from '@mui/icons-material/Mic'
+import type { ThemeMode, AppConfig, HotkeyBinding, AudioDevice } from '@shared/types'
 
 interface SettingsModalProps {
   open: boolean
@@ -183,6 +184,10 @@ export function SettingsModal({ open, onClose }: SettingsModalProps): React.Reac
   const [hotkeyModalOpen, setHotkeyModalOpen] = useState(false)
   const [hotkeyModalTarget, setHotkeyModalTarget] = useState<'dictation' | 'handsFree'>('dictation')
 
+  // 오디오 디바이스
+  const [audioDevices, setAudioDevices] = useState<AudioDevice[]>([])
+  const [selectedDeviceId, setSelectedDeviceId] = useState<string>('default')
+
   // 설정 로드
   useEffect(() => {
     if (!open) return
@@ -193,8 +198,10 @@ export function SettingsModal({ open, onClose }: SettingsModalProps): React.Reac
       window.electronAPI.hotkey.getDictationShortcut(),
       window.electronAPI.hotkey.getHandsFreeShortcut(),
       window.electronAPI.hotkey.isEnabled(),
+      window.electronAPI.audio.getDevices(),
+      window.electronAPI.audio.getSelectedDevice(),
     ])
-      .then(([configResult, dictResult, hfResult, enabledResult]) => {
+      .then(([configResult, dictResult, hfResult, enabledResult, devicesResult, selectedResult]) => {
         if (configResult.success) setConfig(configResult.data)
         if (dictResult.success && dictResult.data) setDictationBinding(dictResult.data)
         if (hfResult.success && hfResult.data) setHandsFreeBinding(hfResult.data)
@@ -202,6 +209,8 @@ export function SettingsModal({ open, onClose }: SettingsModalProps): React.Reac
           setHotkeyGlobalEnabled(enabledResult.data)
           setDictationEnabled(enabledResult.data)
         }
+        if (devicesResult.success) setAudioDevices(devicesResult.data)
+        if (selectedResult.success && selectedResult.data) setSelectedDeviceId(selectedResult.data)
       })
       .finally(() => setLoading(false))
   }, [open])
@@ -412,9 +421,34 @@ export function SettingsModal({ open, onClose }: SettingsModalProps): React.Reac
           {/* ── 오디오 탭 ────────────────────────────── */}
           <TabPanel value={activeTab} index={1}>
             <Box sx={{ display: 'flex', flexDirection: 'column', gap: 2 }}>
-              <Typography variant="body2" color="text.secondary">
-                현재 시스템 기본 마이크를 사용합니다.
-                마이크 선택 및 테스트 기능은 추후 업데이트에서 제공됩니다.
+              <Typography variant="overline" sx={{ color: d3roPalette.text.label, letterSpacing: '1.5px' }}>
+                마이크
+              </Typography>
+
+              <FormControl size="small">
+                <InputLabel>입력 장치</InputLabel>
+                <Select
+                  label="입력 장치"
+                  value={selectedDeviceId}
+                  onChange={(e) => {
+                    const deviceId = e.target.value
+                    setSelectedDeviceId(deviceId)
+                    window.electronAPI.audio.setSelectedDevice({ deviceId })
+                  }}
+                  startAdornment={<MicIcon sx={{ color: d3roPalette.text.inactive, mr: 1, fontSize: 18 }} />}
+                >
+                  {audioDevices.map((device) => (
+                    <MenuItem key={device.deviceId} value={device.deviceId}>
+                      {device.label}{device.isDefault ? ' (기본)' : ''}
+                    </MenuItem>
+                  ))}
+                </Select>
+              </FormControl>
+
+              <Divider sx={{ borderColor: d3roPalette.border.subtle }} />
+
+              <Typography variant="overline" sx={{ color: d3roPalette.text.label, letterSpacing: '1.5px' }}>
+                텍스트 삽입
               </Typography>
 
               <FormControl size="small">