platos: segundo plato por comida (ensalada + salmon)

- MealSlot.secondaryDishId (opcional, aditivo CloudKit); se limpia al
  sustituir/quitar/vaciar/marcar comer fuera y viaja en swaps, copia de
  semana anterior, undo y snapshot KV de iCloud (retrocompatible)
- Picker de hueco lleno: toggle "anadir como segundo plato" + boton para
  quitarlo; HomeViewModel.assignSecondaryDish/removeSecondaryDish
- Se muestra "Plato + Segundo" en calendario, widget y export; la lista
  de la compra incluye los ingredientes del segundo; stats lo cuentan
- Evento analytics secondary_dish_added; strings en 6 idiomas

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013H6bXqGX1ygwib1Dm3n3UG

MealMood/Services/ICloudSyncService.swift

@@ -115,6 +115,7 @@ final class ICloudSyncService {
                             dayOfWeek: $0.dayOfWeek,
                             mealType: $0.mealType,
                             dishId: $0.dishId,
+                            secondaryDishId: $0.secondaryDishId,
                             calendarEventId: $0.calendarEventId,
                             isRuleOverridden: $0.isRuleOverridden
                         )
@@ -210,6 +211,7 @@ final class ICloudSyncService {
                     dayOfWeek: slotPayload.dayOfWeek,
                     mealType: slotPayload.mealType,
                     dishId: slotPayload.dishId,
+                    secondaryDishId: slotPayload.secondaryDishId,
                     calendarEventId: slotPayload.calendarEventId,
                     isRuleOverridden: slotPayload.isRuleOverridden
                 )
@@ -289,6 +291,8 @@ private struct MealSlotPayload: Codable {
     let dayOfWeek: Int
     let mealType: String
     let dishId: UUID?
+    // Optional so payloads written by older installs (no key) still decode.
+    var secondaryDishId: UUID?
     let calendarEventId: String?
     let isRuleOverridden: Bool
 }

MealMood/Services/WidgetDataStore.swift

@@ -26,10 +26,12 @@ enum WidgetDataStore {
         let appDayOfWeek = (weekday + 5) % 7
 
         let meals: [TodayMealData.Meal] = settings.activeMealTypes.map { mealType in
-            let dishId = plan?.slotList.first {
+            let slot = plan?.slotList.first {
                 $0.dayOfWeek == appDayOfWeek && $0.mealType == mealType.rawValue
-            }?.dishId
-            let name = dishId.flatMap { id in dishes.first { $0.id == id }?.name }
+            }
+            let primaryName = slot?.dishId.flatMap { id in dishes.first { $0.id == id }?.name }
+            let secondaryName = slot?.secondaryDishId.flatMap { id in dishes.first { $0.id == id }?.name }
+            let name = primaryName.map { p in secondaryName.map { "\(p) + \($0)" } ?? p }
             return TodayMealData.Meal(
                 type: mealType.rawValue,
                 label: String(localized: String.LocalizationValue(mealType.localizedKey)),