refactor of money utils with new money2 package

frontend/pshared/lib/models/payment/wallet.dart

@@ -7,7 +7,7 @@ class Wallet implements Describable {
   final String id;
   final String walletUserID; // ID or number that we show the user
   final double balance;
-  final Currency currency;
+  final CurrencyCode currency;
   final DateTime calculatedAt;
   final String? depositAddress;
   final ChainNetwork? network;