feat: enhance inventory and pantry features with filtering, sorting, and error handling improvements

flutter/lib/features/pantry/presentation/pantry_screen.dart

@@ -8,6 +8,7 @@ import '../../auth/data/auth_providers.dart';
 import '../../../core/ui/async_state_views.dart';
 import '../data/pantry_providers.dart';
 import '../domain/pantry_item.dart';
+import '../domain/pantry_product.dart';
 
 class PantryScreen extends ConsumerStatefulWidget {
   const PantryScreen({super.key});
@@ -219,6 +220,19 @@ class _PantryScreenState extends ConsumerState<PantryScreen> {
     }
   }
 
+  String _resolveCategory(PantryItem item, Map<int, PantryProduct> productById) {
+    final fromTree = productById[item.productId]?.categoryPath;
+    if (fromTree != null && fromTree.trim().isNotEmpty) {
+      return fromTree;
+    }
+
+    if (item.category != null && item.category!.trim().isNotEmpty) {
+      return item.category!;
+    }
+
+    return 'Ovrigt';
+  }
+
   @override
   Widget build(BuildContext context) {
     final pantryAsync = ref.watch(pantryProvider);
@@ -241,6 +255,7 @@ class _PantryScreenState extends ConsumerState<PantryScreen> {
 
     final pantryItems = pantryAsync.valueOrNull ?? const [];
     final products = productsAsync.valueOrNull ?? const [];
+    final productById = {for (final product in products) product.id: product};
     final pantryProductIds = pantryItems.map((e) => e.productId).toSet();
     final availableProducts = products
         .where((product) => !pantryProductIds.contains(product.id))
@@ -252,9 +267,7 @@ class _PantryScreenState extends ConsumerState<PantryScreen> {
 
     final grouped = <String, List<PantryItem>>{};
     for (final item in pantryItems) {
-      final category = (item.category == null || item.category!.isEmpty)
-          ? 'Ovrigt'
-          : item.category!;
+      final category = _resolveCategory(item, productById);
       grouped.putIfAbsent(category, () => []).add(item);
     }
     final categories = grouped.keys.toList()