Migrate from Core Data to SwiftData

- Replace Core Data with SwiftData for iOS 18+
- Create MoodEntryModel as @Model class replacing MoodEntry entity
- Create SharedModelContainer for App Group container sharing
- Create DataController with CRUD extensions replacing PersistenceController
- Update all views and view models to use MoodEntryModel
- Update widget extension to use SwiftData
- Remove old Core Data files (Persistence*.swift, .xcdatamodeld)
- Add EntryType enum with all entry type cases
- Fix widget label truncation with proper spacing and text scaling

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

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

Shared/Views/SampleEntryView.swift

@@ -8,14 +8,14 @@
 import SwiftUI
 
 struct SampleEntryView: View {
-    @State private var sampleListEntry = PersistenceController.shared.generateObjectNotInArray(forDate: Date(), withMood: Mood.great)
+    @State private var sampleListEntry = DataController.shared.generateObjectNotInArray(forDate: Date(), withMood: Mood.great)
     @AppStorage(UserDefaultsStore.Keys.theme.rawValue, store: GroupUserDefaults.groupDefaults) private var theme: Theme = .system
     @AppStorage(UserDefaultsStore.Keys.textColor.rawValue, store: GroupUserDefaults.groupDefaults) private var textColor: Color = DefaultTextColor.textColor
-    
+
     var body: some View {
         ZStack {
             theme.currentTheme.secondaryBGColor
-            
+
             VStack {
                 HStack {
                     Spacer()
@@ -24,7 +24,7 @@ struct SampleEntryView: View {
                         .frame(width: 20, height: 20, alignment: .trailing)
                         .foregroundColor(Color(UIColor.systemGray))
                         .onTapGesture {
-                            sampleListEntry = PersistenceController.shared.generateObjectNotInArray(forDate: Date(), withMood: sampleListEntry.mood.next)
+                            sampleListEntry = DataController.shared.generateObjectNotInArray(forDate: Date(), withMood: sampleListEntry.mood.next)
                         }
                 }
                 Spacer()