feat: unified food calendar — extend home screen to future dates + planned meals

Phase 1: date strip now covers today + 7 future days; right chevron enabled;
future pills rendered in lighter style.

Phase 2: home screen shows DateContext (past/today/future):
- future dates: hide calorie ring + macros, show PlanningBanner
- plannedMealsProvider derives from cached menuProvider (no extra API call)
- _MealCard shows ghost PlannedSlotTile for unconfirmed menu slots
- "Mark as eaten" creates a diary entry (source: menu_plan) via existing API

New l10n keys (12 locales): planningForDate, markAsEaten, plannedMealLabel

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/lib/features/home/home_provider.dart

@@ -2,6 +2,8 @@ import 'package:flutter_riverpod/flutter_riverpod.dart';
 
 import '../../features/scan/recognition_service.dart';
 import '../../shared/models/home_summary.dart';
+import '../../shared/models/menu.dart';
+import '../menu/menu_provider.dart';
 import 'home_service.dart';
 
 // ── Selected date (persists while app is open) ────────────────
@@ -76,3 +78,21 @@ final allJobsProvider =
     StateNotifierProvider<AllJobsNotifier, AsyncValue<List<DishJobSummary>>>(
   (ref) => AllJobsNotifier(ref.read(recognitionServiceProvider)),
 );
+
+// ── Planned meals from menu ────────────────────────────────────
+
+/// Returns planned [MealSlot]s from the menu plan for [dateString].
+/// Derives from the already-cached weekly menu — no extra network call.
+/// Returns an empty list when no plan exists for that week.
+final plannedMealsProvider =
+    Provider.family<List<MealSlot>, String>((ref, dateString) {
+  final date = DateTime.parse(dateString);
+  final weekString = isoWeekString(date);
+  final menuState = ref.watch(menuProvider(weekString));
+  final plan = menuState.valueOrNull;
+  if (plan == null) return [];
+  for (final day in plan.days) {
+    if (day.date == dateString) return day.meals;
+  }
+  return [];
+});