refactor: Remove PantryProduct class and simplify category resolution in PantryScreen

flutter/lib/features/pantry/domain/pantry_item.dart

@@ -5,6 +5,7 @@ class PantryItem {
   final String? canonicalName;
   final String? category;
   final int? categoryId;
+  final String? categoryPath;
   final String? location;
 
   const PantryItem({
@@ -14,6 +15,7 @@ class PantryItem {
     this.canonicalName,
     this.category,
     this.categoryId,
+    this.categoryPath,
     this.location,
   });
 
@@ -24,6 +26,17 @@ class PantryItem {
     return productName;
   }
 
+  String? get l1CategoryOrNull {
+    final path = categoryPath?.trim();
+    if (path != null && path.isNotEmpty) {
+      return path.split('>').first.trim();
+    }
+    if (category != null && category!.trim().isNotEmpty) {
+      return category!.trim();
+    }
+    return null;
+  }
+
   factory PantryItem.fromJson(Map<String, dynamic> json) {
     final product = json['product'] as Map<String, dynamic>? ?? {};
     return PantryItem(
@@ -33,7 +46,25 @@ class PantryItem {
       canonicalName: product['canonicalName']?.toString(),
       category: product['category']?.toString(),
       categoryId: (product['categoryId'] as num?)?.toInt(),
+      categoryPath: _buildCategoryPath(product['categoryRef']),
       location: json['location']?.toString(),
     );
   }
+
+  static String? _buildCategoryPath(dynamic rawCategoryRef) {
+    if (rawCategoryRef is! Map<String, dynamic>) return null;
+
+    final names = <String>[];
+    dynamic current = rawCategoryRef;
+    while (current is Map<String, dynamic>) {
+      final name = current['name']?.toString().trim();
+      if (name != null && name.isNotEmpty) {
+        names.add(name);
+      }
+      current = current['parent'];
+    }
+
+    if (names.isEmpty) return null;
+    return names.reversed.join(' > ');
+  }
 }

flutter/lib/features/pantry/domain/pantry_product.dart

@@ -1,55 +0,0 @@
-class PantryProduct {
-  final int id;
-  final String name;
-  final String? canonicalName;
-  final String? category;
-  final int? categoryId;
-  final String? categoryPath;
-
-  const PantryProduct({
-    required this.id,
-    required this.name,
-    this.canonicalName,
-    this.category,
-    this.categoryId,
-    this.categoryPath,
-  });
-
-  String get displayName {
-    if (canonicalName != null && canonicalName!.trim().isNotEmpty) {
-      return canonicalName!;
-    }
-    return name;
-  }
-
-  factory PantryProduct.fromJson(Map<String, dynamic> json) {
-    final categoryRef = json['categoryRef'];
-    final path = _buildCategoryPath(categoryRef);
-
-    return PantryProduct(
-      id: (json['id'] as num).toInt(),
-      name: (json['name'] ?? '').toString(),
-      canonicalName: json['canonicalName']?.toString(),
-      category: json['category']?.toString(),
-      categoryId: (json['categoryId'] as num?)?.toInt(),
-      categoryPath: path,
-    );
-  }
-
-  static String? _buildCategoryPath(dynamic rawCategoryRef) {
-    if (rawCategoryRef is! Map<String, dynamic>) return null;
-
-    final names = <String>[];
-    dynamic current = rawCategoryRef;
-    while (current is Map<String, dynamic>) {
-      final name = current['name']?.toString().trim();
-      if (name != null && name.isNotEmpty) {
-        names.insert(0, name);
-      }
-      current = current['parent'];
-    }
-
-    if (names.isEmpty) return null;
-    return names.join(' > ');
-  }
-}