implemented backend wallet service connection

frontend/pweb/lib/widgets/error/snackbar.dart

@@ -3,6 +3,7 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 
 import 'package:pweb/utils/error_handler.dart';
+import 'package:pweb/utils/snackbar.dart';
 import 'package:pweb/widgets/error/content.dart'; 
 
 import 'package:pweb/generated/i18n/app_localizations.dart';
@@ -52,13 +53,18 @@ Future<T?> executeActionWithNotification<T>({
   required BuildContext context,
   required Future<T> Function() action,
   required String errorMessage,
+  String? successMessage,
   int delaySeconds = 3,
 }) async {
   final scaffoldMessenger = ScaffoldMessenger.of(context);
   final localizations = AppLocalizations.of(context)!;
 
   try {
-    return await action();
+    final res = await action();
+    if (successMessage != null) {
+      notifyUserX(scaffoldMessenger, successMessage, delaySeconds: delaySeconds);
+    }
+    return res;
   } catch (e) {
     // Report the error using your existing notifier.
     notifyUserOfErrorX(