feat: #13 公开商品 API 补充 code/barcode/batch.quantity，报错反馈携带商品和门店信息

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/lib/screens/public/public_product_screen.dart

@@ -70,13 +70,22 @@ class _PublicProductScreenState extends State<PublicProductScreen> {
         title: title,
         hint: hint,
         onSubmit: (msg) async {
+          final shopNo = (_data?['shop'] as Map<String, dynamic>?)?['code'] as String? ?? '';
+          final productName = _data?['name'] as String? ?? '';
+          final productCode = _data?['code'] as String? ?? '';
+          final productInfo = [
+            if (productName.isNotEmpty) productName,
+            if (productCode.isNotEmpty) productCode,
+            if (widget.publicId.isNotEmpty) widget.publicId,
+          ].join(' / ');
           await _dio.post(
             '${AppConfig.apiBaseUrl}/public/errors',
             data: {
               'error_type': errorType,
               'error_msg': msg,
               'platform': 'web-scan',
-              'shop_no': (_data?['shop'] as Map<String, dynamic>?)?['code'] as String? ?? '',
+              'shop_no': shopNo,
+              if (productInfo.isNotEmpty) 'product_info': productInfo,
             },
           );
         },