create order -> upload bill

lib/features/orders/domain/repositories/order_repository.dart

@@ -26,4 +26,10 @@ abstract class OrderRepository {
 
   /// Generate QR code for payment
   Future<Map<String, dynamic>> generateQrCode(String orderId);
+
+  /// Upload bill/invoice file
+  Future<Map<String, dynamic>> uploadBill({
+    required String filePath,
+    required String orderId,
+  });
 }