Refactor StoreKit 2 subscription system and add interactive vote widget

## StoreKit 2 Refactor
- Rewrote IAPManager with clean enum-based state model (SubscriptionState)
- Added native SubscriptionStoreView for iOS 17+ purchase UI
- Subscription status now checked on every app launch
- Synced subscription status to UserDefaults for widget access
- Simplified PurchaseButtonView and IAPWarningView
- Removed unused StatusInfoView

## Interactive Vote Widget
- New FeelsVoteWidget with App Intents for mood voting
- Subscribers can vote directly from widget, shows stats after voting
- Non-subscribers see "Tap to subscribe" which opens subscription store
- Added feels:// URL scheme for deep linking

## Firebase Removal
- Commented out Firebase imports and initialization
- EventLogger now prints to console in DEBUG mode only

## Other Changes
- Added fallback for Core Data when App Group unavailable
- Added new localization strings for subscription UI
- Updated entitlements and Info.plist

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Shared/FeelsApp.swift

@@ -17,6 +17,7 @@ struct FeelsApp: App {
     let persistenceController = PersistenceController.shared
     @StateObject var iapManager = IAPManager()
     @AppStorage(UserDefaultsStore.Keys.firstLaunchDate.rawValue, store: GroupUserDefaults.groupDefaults) private var firstLaunchDate = Date()
+    @State private var showSubscriptionFromWidget = false
 
     init() {
         BGTaskScheduler.shared.cancelAllTaskRequests()
@@ -38,14 +39,27 @@ struct FeelsApp: App {
                         customizeView: CustomizeView())
             .environment(\.managedObjectContext, persistenceController.viewContext)
             .environmentObject(iapManager)
+            .sheet(isPresented: $showSubscriptionFromWidget) {
+                FeelsSubscriptionStoreView()
+                    .environmentObject(iapManager)
+            }
+            .onOpenURL { url in
+                if url.scheme == "feels" && url.host == "subscribe" {
+                    showSubscriptionFromWidget = true
+                }
+            }
         }.onChange(of: scenePhase) { phase in
             if phase == .background {
                 //BGTask.scheduleBackgroundProcessing()
                 WidgetCenter.shared.reloadAllTimelines()
             }
-            
+
             if phase == .active {
                 UIApplication.shared.applicationIconBadgeNumber = 0
+                // Check subscription status on each app launch
+                Task {
+                    await iapManager.checkSubscriptionStatus()
+                }
             }
         }
     }