2.0: breakfast and snack meal types across the app

- MealType gains breakfast/snack (chronological order drives slot/row order).
- AppSettings.activeMealTypes: single source of truth for enabled meals, backed
  by new optional enabledMealTypesRaw with legacy mealWindows fallback —
  additive migration, keeps pre-2.0 installs and iCloud snapshots working.
  Legacy field kept coherent by the setter. time(for:) resolves per-meal event
  times (breakfast 8:00 / snack 17:00 defaults on old stores).
- Replaced the 5 duplicated mealWindows→[MealType] derivations (slot sync,
  default plan creation, week calendar, export view) with activeMealTypes.
- CalendarService: per-type event names and times.
- Export styles: per-type accent colors and gradients.
- Widget: generic meals list (N rows) instead of hardcoded lunch/dinner;
  compact families fall back to main meals when >2 are active.
- Settings: 4 meal toggles (min 1) replace the 3-option picker.
- Onboarding: meal step is now multi-select over the 4 types.
- iCloud sync: enabledMealTypesRaw synced (optional, pre-2.0 compatible).
- Localized breakfast/snack in all 6 languages.

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

MealMood/Views/Onboarding/MealWindowsStepView.swift

@@ -1,7 +1,7 @@
 import SwiftUI
 
 struct MealWindowsStepView: View {
-    @Binding var selection: MealWindows
+    @Binding var selection: Set<MealType>
     var onNext: () -> Void
 
     var body: some View {
@@ -15,14 +15,21 @@ struct MealWindowsStepView: View {
                 .padding(.top, 12)
 
             VStack(spacing: 12) {
-                ForEach(MealWindows.allCases, id: \.self) { option in
+                ForEach(MealType.allCases, id: \.self) { mealType in
                     SelectionCard(
-                        icon: option.icon,
-                        title: optionTitle(option),
-                        isSelected: selection == option
+                        icon: mealType.icon,
+                        title: optionTitle(mealType),
+                        isSelected: selection.contains(mealType)
                     ) {
                         withAnimation(.spring(response: 0.3)) {
-                            selection = option
+                            if selection.contains(mealType) {
+                                // Keep at least one meal selected.
+                                if selection.count > 1 {
+                                    selection.remove(mealType)
+                                }
+                            } else {
+                                selection.insert(mealType)
+                            }
                         }
                         HapticManager.shared.selection()
                     }
@@ -38,12 +45,15 @@ struct MealWindowsStepView: View {
         .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .top)
     }
 
-    private func optionTitle(_ option: MealWindows) -> String {
-        switch option {
-        case .dinnerOnly: return "🌙 \(String(localized: "meal_windows_dinner_only"))"
-        case .lunchOnly: return "☀️ \(String(localized: "meal_windows_lunch_only"))"
-        case .both: return "🌞🌙 \(String(localized: "meal_windows_both"))"
+    private func optionTitle(_ mealType: MealType) -> String {
+        let emoji: String
+        switch mealType {
+        case .breakfast: emoji = "☕️"
+        case .lunch: emoji = "🌞"
+        case .snack: emoji = "🍎"
+        case .dinner: emoji = "🌙"
         }
+        return "\(emoji) \(String(localized: String.LocalizationValue(mealType.localizedKey)))"
     }
 }