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/Persisence/DataControllerADD.swift

@@ -0,0 +1,77 @@
+//
+//  DataControllerADD.swift
+//  Feels
+//
+//  SwiftData CREATE operations.
+//
+
+import SwiftData
+import Foundation
+
+extension DataController {
+    func add(mood: Mood, forDate date: Date, entryType: EntryType) {
+        // Delete existing entry for this date if present
+        if let existing = getEntry(byDate: date) {
+            modelContext.delete(existing)
+            try? modelContext.save()
+        }
+
+        let entry = MoodEntryModel(
+            forDate: date,
+            mood: mood,
+            entryType: entryType
+        )
+
+        modelContext.insert(entry)
+        EventLogger.log(event: "add_entry", withData: ["entry_type": entryType.rawValue])
+        saveAndRunDataListeners()
+    }
+
+    func fillInMissingDates() {
+        let currentOnboarding = UserDefaultsStore.getOnboarding()
+        var endDate = ShowBasedOnVoteLogics.getCurrentVotingDate(onboardingData: currentOnboarding)
+        // Since it's for views, take away the last date so vote is enabled
+        endDate = Calendar.current.date(byAdding: .day, value: -1, to: endDate)!
+
+        let descriptor = FetchDescriptor<MoodEntryModel>(
+            sortBy: [SortDescriptor(\.forDate, order: .reverse)]
+        )
+
+        guard let entries = try? modelContext.fetch(descriptor),
+              let firstEntry = entries.last else { return }
+
+        let allDates: [Date] = Date.dates(from: firstEntry.forDate, toDate: endDate, includingToDate: true).map {
+            Calendar.current.date(bySettingHour: 0, minute: 0, second: 0, of: $0)!
+        }
+
+        let existingDates: Set<Date> = Set(entries.map {
+            Calendar.current.date(bySettingHour: 0, minute: 0, second: 0, of: $0.forDate)!
+        })
+
+        let missing = Array(Set(allDates).subtracting(existingDates)).sorted(by: >)
+
+        for date in missing {
+            // Add 12 hours to avoid UTC offset issues
+            let adjustedDate = Calendar.current.date(byAdding: .hour, value: 12, to: date)!
+            add(mood: .missing, forDate: adjustedDate, entryType: .filledInMissing)
+        }
+
+        if !missing.isEmpty {
+            EventLogger.log(event: "filled_in_missing_entries", withData: ["count": missing.count])
+        }
+    }
+
+    func fixWrongWeekdays() {
+        let data = getData(startDate: Date(timeIntervalSince1970: 0), endDate: Date(), includedDays: [])
+        for entry in data {
+            entry.weekDay = Calendar.current.component(.weekday, from: entry.forDate)
+        }
+        save()
+    }
+
+    func removeNoForDates() {
+        // Note: With SwiftData's non-optional forDate, this is essentially a no-op
+        // Keeping for API compatibility
+        EventLogger.log(event: "removed_entry_no_for_date", withData: ["count": 0])
+    }
+}