Fix 7 data mutation layer risks identified in audit

- save()/saveAndRunDataListeners() now return @discardableResult Bool;
  listeners only fire on successful save
- MoodLogger.updateMood() now recalculates streak, updates Live Activity,
  and notifies watch (was missing these side effects)
- CSV import uses new addBatch()/importMoods() for O(1) side effects
  instead of O(n) per-row widget reloads and streak calcs
- Foreground task ordering: fillInMissingDates() now runs before
  removeDuplicates() so backfill-created duplicates are caught same cycle
- WidgetMoodSaver deletes ALL entries for date (was fetchLimit=1, leaving
  CloudKit sync duplicates behind)
- cleanupPhotoIfNeeded logs warning on failed photo deletion instead of
  silently orphaning files

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Shared/FeelsApp.swift

@@ -21,6 +21,7 @@ struct FeelsApp: App {
     @StateObject var healthKitManager = HealthKitManager.shared
     @AppStorage(UserDefaultsStore.Keys.firstLaunchDate.rawValue, store: GroupUserDefaults.groupDefaults) private var firstLaunchDate = Date()
     @State private var showSubscriptionFromWidget = false
+    @State private var showStorageFallbackAlert = SharedModelContainer.isUsingInMemoryFallback
 
     init() {
         AnalyticsManager.shared.configure()
@@ -61,6 +62,17 @@ struct FeelsApp: App {
                         showSubscriptionFromWidget = true
                     }
                 }
+                .alert("Data Storage Unavailable",
+                       isPresented: $showStorageFallbackAlert) {
+                    Button("OK", role: .cancel) { }
+                } message: {
+                    Text("Your mood data cannot be saved permanently. Please restart the app. If the problem persists, reinstall the app.")
+                }
+                .onAppear {
+                    if SharedModelContainer.isUsingInMemoryFallback {
+                        AnalyticsManager.shared.track(.storageFallbackActivated)
+                    }
+                }
 
                 // Lock screen overlay
                 if authManager.isLockEnabled && !authManager.isUnlocked {
@@ -93,12 +105,12 @@ struct FeelsApp: App {
                     // Refresh from disk to pick up widget/watch changes
                     DataController.shared.refreshFromDisk()
 
-                    // Clean up any duplicate entries first
-                    DataController.shared.removeDuplicates()
-
                     // Fill in any missing dates (moved from AppDelegate)
                     DataController.shared.fillInMissingDates()
 
+                    // Clean up any duplicate entries (after backfill so backfill dupes are caught)
+                    DataController.shared.removeDuplicates()
+
                     // Reschedule notifications for new title
                     LocalNotification.rescheduleNotifiations()