feat: Add TripImageService for automatic trip image management

- Implemented TripImageService to load missing images for trips, reload images, and clean up unused images.
- Added functionality to get image statistics and clean up duplicate images.
- Created utility scripts for manual image cleanup and diagnostics in Firebase Storage.
- Introduced tests for image loading optimization and photo quality algorithms.
- Updated dependencies in pubspec.yaml and pubspec.lock for image handling.

lib/repositories/expense_repository.dart

@@ -16,15 +16,19 @@ class ExpenseRepository {
 
   // Stream des dépenses d'un groupe
   Stream<List<Expense>> getExpensesStream(String groupId) {
+    // Utiliser une requête simple pour éviter les problèmes d'index
     return _expensesCollection
         .where('groupId', isEqualTo: groupId)
-        .where('isArchived', isEqualTo: false)
-        .orderBy('createdAt', descending: true)
         .snapshots()
         .map((snapshot) {
-      return snapshot.docs
+      final expenses = snapshot.docs
           .map((doc) => Expense.fromMap(doc.data() as Map<String, dynamic>, doc.id))
+          .where((expense) => !expense.isArchived) // Filtrer côté client
           .toList();
+      
+      // Trier côté client par date de création (plus récent en premier)
+      expenses.sort((a, b) => b.createdAt.compareTo(a.createdAt));
+      return expenses;
     }).handleError((error) {
       _errorService.logError('ExpenseRepository', 'Erreur stream expenses: $error');
       return <Expense>[];