chore(cleanup): NIRS/VIVAMYO 세트 완전 제거 (Category A · 사용자 요청)

배경: NIRS 는 초기 iOS 앱에서 이식했으나 현재 완전 미사용. Piezo 만 실사용.

완전 제거 (6 파일):
  · managers/NirsManager.kt (94 L)
  · managers/NirsCalcEngine.kt (206 L)
  · models/NirsConstants.kt (49 L)
  · models/NirsData.kt (106 L · NirsMcjPacket · NirsMagResponse · NirsOxyResult)
  · ui/views/monitoring/VivamyoMonitoringView.kt (497 L)
  · ui/views/calibration/CalibrationView.kt (216 L) + calibration/ 디렉토리

부분 편집:
  · AppState.kt      — NirsManager import · NIRS_CALIBRATION/VIVAMYO_MONITORING enum ·
                       calibrationComplete() · sensor 분기 3곳 (goHome/enterDemoMode/
                       deviceConnected/backToMonitoring) 모두 PIEZO 로 단순화
  · MainActivity.kt  — CalibrationView/VivamyoMonitoringView import + Crossfade branch +
                       back-handler branch 삭제
  · BleManager.kt    — 콜백 4개 (onNirsPowerOn/SensorActivated/MagReceived/McjReceived) ·
                       sendRawWrite when-branch 4개 · NIRS Commands 섹션 5 함수 ·
                       RX branch 4개 삭제
  · MeasurementService.kt — performNirsMeasurement 제거 · performMeasurement 단순화 ·
                       stop() 콜백 정리 · SensorMode 유지 (센서 추가 대비)
  · SensorMode.kt    — NIRS enum value 삭제 · PIEZO 만 남음 · UserStorage 는
                       valueOf 실패 시 PIEZO fallback 이라 마이그레이션 불필요
  · SensorSelectView.kt — NIRS SensorCard 제거
  · strings.xml × 2  — sensor_nirs_desc · calibration_* 10개 · vivamyo_* 17개 삭제
                       (calibration_continue 는 PiezoPersonalization 사용 → 유지)

합계: 약 1,300 LOC 감소.
빌드: BUILD SUCCESSFUL 17s.

app/src/main/java/com/medithings/vesiscan/MainActivity.kt

@@ -24,13 +24,11 @@ import com.medithings.vesiscan.services.KeychainService
 import com.medithings.vesiscan.services.NotificationService
 import com.medithings.vesiscan.R
 import com.medithings.vesiscan.ui.theme.Medilightv2androidTheme
-import com.medithings.vesiscan.ui.views.calibration.CalibrationView
 import com.medithings.vesiscan.ui.views.connection.DeviceScanView
 import com.medithings.vesiscan.ui.views.history.MeasurementHistoryView
 import com.medithings.vesiscan.ui.views.home.HomeView
 import com.medithings.vesiscan.ui.views.monitoring.PlacementGuideView
 import com.medithings.vesiscan.ui.views.monitoring.PiezoMonitoringView
-import com.medithings.vesiscan.ui.views.monitoring.VivamyoMonitoringView
 import com.medithings.vesiscan.ui.views.monitoring.UrineCameraScreen
 import com.medithings.vesiscan.ui.views.monitoring.VoidingDiaryView
 import com.medithings.vesiscan.ui.views.onboarding.OnboardingView
@@ -155,8 +153,6 @@ fun MedilightApp(modifier: Modifier = Modifier) {
             AppScreen.FIRMWARE_UPDATE -> appState.currentScreen = AppScreen.HOME
             // 기타
             AppScreen.SENSOR_SELECT -> appState.currentScreen = AppScreen.HOME
-            AppScreen.VIVAMYO_MONITORING -> appState.currentScreen = AppScreen.HOME
-            AppScreen.NIRS_CALIBRATION -> appState.currentScreen = AppScreen.DEVICE_SCAN
             // 온보딩/등록 (뒤로가기 막지 않되 Home으로)
             else -> appState.currentScreen = AppScreen.HOME
         }
@@ -175,12 +171,10 @@ fun MedilightApp(modifier: Modifier = Modifier) {
             AppScreen.HOME -> HomeView(appState)
             AppScreen.SENSOR_SELECT -> SensorSelectView(appState)
             AppScreen.DEVICE_SCAN -> DeviceScanView(appState)
-            AppScreen.NIRS_CALIBRATION -> CalibrationView(appState)
             AppScreen.PIEZO_PERSONALIZATION -> PiezoPersonalizationView(appState)
             AppScreen.PLACEMENT_GUIDE -> PlacementGuideView(appState)
             AppScreen.PIN_SETUP -> PinView(appState, PinMode.SETUP, context)
             AppScreen.PIN_ENTRY -> PinView(appState, PinMode.ENTER, context)
-            AppScreen.VIVAMYO_MONITORING -> VivamyoMonitoringView(appState)
             AppScreen.PIEZO_MONITORING -> PiezoMonitoringView(appState)
             AppScreen.MEASUREMENT_HISTORY -> MeasurementHistoryView(appState)
             AppScreen.VOIDING_DIARY -> VoidingDiaryView(onBack = { appState.currentScreen = AppScreen.HOME })