new plus button

lib/models/shop.dart

@@ -8,22 +8,47 @@ class Shop {
     required this.shoppedAt,
     required this.total,
     required this.itemCount,
+    this.name,
     this.receiptImagePath,
+    this.tags = const [],
   });
 
   final int id;
   final String supermarket;
+  final String? name;
   final DateTime shoppedAt;
   final double total;
   final int itemCount;
   final String? receiptImagePath;
+  final List<String> tags;
+
+  String get displayName {
+    final tripName = name?.trim();
+    if (tripName != null && tripName.isNotEmpty) return tripName;
+    return supermarket;
+  }
+
+  Shop copyWith({String? name, bool clearName = false, List<String>? tags}) {
+    return Shop(
+      id: id,
+      supermarket: supermarket,
+      shoppedAt: shoppedAt,
+      total: total,
+      itemCount: itemCount,
+      receiptImagePath: receiptImagePath,
+      name: clearName ? null : (name ?? this.name),
+      tags: tags ?? this.tags,
+    );
+  }
 
   factory Shop.fromMap(Map<String, Object?> map) {
+    final rawName = (map['name'] as String?)?.trim();
     return Shop(
       id: map['id']! as int,
       supermarket: map['supermarket']! as String,
+      name: (rawName == null || rawName.isEmpty) ? null : rawName,
       shoppedAt: DateTime.parse(map['shopped_at']! as String),
-      total: (map['total']! as num).toDouble(),
+      total: (map['total'] as num).toDouble(),
       itemCount: (map['item_count'] as num?)?.toInt() ?? 0,
       receiptImagePath: map['receipt_image_path'] as String?,
     );
@@ -55,7 +80,7 @@ class ShopItem {
       shopId: map['shop_id']! as int,
       productId: map['product_id']! as int,
       name: map['name']! as String,
-      price: (map['price']! as num).toDouble(),
+      price: (map['price'] as num).toDouble(),
       quantity: map['quantity'] as int?,
       unitPrice: (map['unit_price'] as num?)?.toDouble(),
     );