feat: add meal planning feature with API integration

- Introduced MealPlanApiPaths for handling meal plan related API endpoints.
- Added MealPlanScreen for displaying and managing meal plans.
- Implemented MealPlanRepository for fetching and updating meal plan data.
- Created data models: MealPlanEntry, MealPlanRecipe, InventoryCompareItem, ShoppingItem, and MealPlanDashboard.
- Integrated meal plan functionality into the app router and UI.
- Updated localization files for meal plan related strings in English and Swedish.
- Added state management for meal plan using Riverpod.

flutter/lib/features/meal_plan/data/meal_plan_providers.dart

@@ -0,0 +1,41 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+
+import '../../../core/api/api_providers.dart';
+import '../../../core/api/guarded_api_call.dart';
+import '../../auth/data/auth_providers.dart';
+import '../domain/meal_plan_dashboard.dart';
+import '../domain/meal_plan_week.dart';
+import 'meal_plan_repository.dart';
+
+final mealPlanRepositoryProvider = Provider<MealPlanRepository>((ref) {
+  return MealPlanRepository(ref.watch(apiClientProvider));
+});
+
+final mealPlanWeekOffsetProvider = StateProvider<int>((ref) => 0);
+
+final mealPlanWeekProvider = Provider<MealPlanWeek>((ref) {
+  final offset = ref.watch(mealPlanWeekOffsetProvider);
+  return MealPlanWeek.fromOffset(offset);
+});
+
+final mealPlanDashboardProvider = FutureProvider<MealPlanDashboard>((ref) async {
+  final week = ref.watch(mealPlanWeekProvider);
+  final token = await ref.watch(authStateProvider.future);
+
+  return guardedApiCall(ref, () async {
+    final repository = ref.read(mealPlanRepositoryProvider);
+    final entries = await repository.fetchEntries(week.fromIso, week.toIso, token: token);
+    final shoppingItems = await repository.fetchShoppingList(week.fromIso, week.toIso, token: token);
+    final inventoryCompareItems = await repository.fetchInventoryCompare(
+      week.fromIso,
+      week.toIso,
+      token: token,
+    );
+
+    return MealPlanDashboard(
+      entries: entries,
+      shoppingItems: shoppingItems,
+      inventoryCompareItems: inventoryCompareItems,
+    );
+  });
+});