feat: Improve user experience after voting on proposals

- Redirect users to the proposal detail page with a success
  message after a successful vote, improving feedback.
- Automatically remove the success message from the URL after a
  short time to avoid URL clutter and maintain a clean browsing
  experience.
- Add a success alert message on the proposal detail page to
  provide immediate visual confirmation of a successful vote.
- Improve the visual presentation of the votes list on the
  proposal detail page by adding top margin for better spacing.

actix_mvc_app/src/views/governance/proposal_detail.html

@@ -240,7 +240,7 @@
         </div>
 
         <!-- Votes List -->
-        <div class="row">
+        <div class="row mt-4">
             <div class="col-12">
                 <div class="card shadow-sm">
                     <div class="card-header bg-light d-flex justify-content-between align-items-center flex-wrap">
@@ -338,6 +338,23 @@
     {% block scripts %}
     <script>
         document.addEventListener('DOMContentLoaded', function () {
+            // Remove query parameters from URL without refreshing the page
+            if (window.location.search.includes('vote_success=true')) {
+                const newUrl = window.location.pathname;
+                window.history.replaceState({}, document.title, newUrl);
+                
+                // Auto-hide the success alert after 5 seconds
+                const successAlert = document.querySelector('.alert-success');
+                if (successAlert) {
+                    setTimeout(function() {
+                        successAlert.classList.remove('show');
+                        setTimeout(function() {
+                            successAlert.remove();
+                        }, 500);
+                    }, 5000);
+                }
+            }
+            
             // Vote filtering using data-filter attributes
             const filterButtons = document.querySelectorAll('[data-filter]');
             const voteRows = document.querySelectorAll('.vote-row');