feat:add frames

lib/feature/shop/domain/entities/frame.dart

@@ -0,0 +1,31 @@
+/// یک قابِ آواتار (کازمتیک). owned یعنی قابلِ انتخاب.
+class AvatarFrame {
+  final String id;
+  final String title;
+  final int priceCoins;
+  final bool vip;
+  final bool owned;
+
+  const AvatarFrame({
+    required this.id,
+    required this.title,
+    required this.priceCoins,
+    required this.vip,
+    required this.owned,
+  });
+
+  factory AvatarFrame.fromJson(Map<String, dynamic> j) => AvatarFrame(
+        id: (j['id'] ?? '') as String,
+        title: (j['title'] ?? '') as String,
+        priceCoins: (j['price_coins'] ?? 0) as int,
+        vip: (j['vip'] ?? false) as bool,
+        owned: (j['owned'] ?? false) as bool,
+      );
+}
+
+/// کاتالوگِ قاب‌ها + قابِ انتخابیِ کاربر.
+class FrameCatalog {
+  final List<AvatarFrame> frames;
+  final String selected;
+  const FrameCatalog({required this.frames, required this.selected});
+}