2.0: CloudKit private-database sync replaces KV snapshot sync

Foundation for 2.1 family sharing (CKShare needs these models + container).
SwiftData cannot share across Apple IDs today, so 2.0 ships true multi-device
sync for the same account instead:

- Models made CloudKit-compatible: dropped @Attribute(.unique) on all 5,
  inline defaults on every attribute, WeekPlan.slots stored as optional
  relationship (name preserved → lightweight migration) with non-optional
  slotList facade; ~73 call sites renamed.
- Container: cloudKitDatabase .automatic, falling back to the local-only
  store when CloudKit is unavailable; failures recorded to Crashlytics.
- Entitlements: iCloud CloudKit service (container already existed);
  remote-notification background mode for push-driven sync.
- Legacy KV snapshot sync (ICloudSyncService) stays inert when CloudKit is
  active — kept only for 1.x devices.
- DeduplicationService collapses cross-device duplicates deterministically on
  launch (settings singleton, default tags with tagId remapping, same-week
  plans).
- Note: AppSettings.isPremium now syncs across same-Apple-ID devices; StoreKit
  (PremiumSyncService + Transaction.updates) remains the source of truth and
  reconciles on every launch/foreground.

All 21 unit tests pass, including ICloudSyncPremiumIsolationTests.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BkanrydYtrme8wipTzWssG

MealMood/ViewModels/DishViewModel.swift

@@ -109,7 +109,7 @@ final class DishViewModel: ObservableObject {
 
     func canDelete(currentPlan: WeekPlan?) -> Bool {
         guard let dish = editingDish, let plan = currentPlan else { return true }
-        return !plan.slots.contains { $0.dishId == dish.id }
+        return !plan.slotList.contains { $0.dishId == dish.id }
     }
 
     private func isDishAssignedInCurrentWeek(dishId: UUID, context: ModelContext) -> Bool {
@@ -124,6 +124,6 @@ final class DishViewModel: ObservableObject {
             return false
         }
 
-        return currentPlan.slots.contains { $0.dishId == dishId }
+        return currentPlan.slotList.contains { $0.dishId == dishId }
     }
 }