+ quotation provider

frontend/pshared/lib/models/payment/methods/russian_bank.dart

@@ -2,7 +2,7 @@ import 'package:pshared/models/payment/methods/data.dart';
 import 'package:pshared/models/payment/type.dart';
 
 
-class RussianBankAccountPaymentMethod extends PaymentMethodData {
+class RussianBankAccountPaymentMethod implements PaymentMethodData {
   @override
   final PaymentType type = PaymentType.bankAccount;
 
@@ -13,8 +13,10 @@ class RussianBankAccountPaymentMethod extends PaymentMethodData {
   final String bik;          
   final String accountNumber;
   final String correspondentAccount;
+  @override
+  final Map<String, String>? metadata;
 
-  RussianBankAccountPaymentMethod({
+  const RussianBankAccountPaymentMethod({
     required this.recipientName,
     required this.inn,
     required this.kpp,
@@ -22,5 +24,6 @@ class RussianBankAccountPaymentMethod extends PaymentMethodData {
     required this.bik,
     required this.accountNumber,
     required this.correspondentAccount,
+    this.metadata,
   });
 }