Add click handler for refresh button in portal

The refresh button in the top bar had no click handler attached.
Now it reloads the current page data when clicked.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

portal/portal.js

@@ -39,6 +39,9 @@ const Portal = {
     // Setup sidebar toggle
     this.setupSidebarToggle();
 
+    // Setup refresh button
+    this.setupRefreshButton();
+
     // Load initial data
     await this.loadDashboard();
 
@@ -240,6 +243,16 @@ const Portal = {
     });
   },
 
+  // Setup refresh button
+  setupRefreshButton() {
+    const btn = document.getElementById('refreshBtn');
+    if (btn) {
+      btn.addEventListener('click', () => {
+        this.loadPageData(this.currentPage);
+      });
+    }
+  },
+
   // Handle hash change
   handleHashChange() {
     const hash = window.location.hash.slice(1) || 'dashboard';