fix(ui): status panel empty on login / requires double-click to open

showDashboard now explicitly resets the status panel to display:none and
clears its innerHTML on every call. This prevents a stale display value
from a previous session making toggleStatusPanel think it is already open
(causing it to hide on the first click instead of showing).

Also cancel the status refresh timer on logout.

public/app.js

@@ -209,6 +209,7 @@ async function handleLogin(e) {
 async function handleLogout() {
   try {
     stopSSE();
+    if (statusRefreshHandle) { clearInterval(statusRefreshHandle); statusRefreshHandle = null; }
     await fetch('/api/auth/logout', {
       method: 'POST',
       headers: csrfToken ? { 'X-CSRF-Token': csrfToken } : {}
@@ -232,6 +233,10 @@ function showDashboard() {
   document.getElementById('login-container').style.display = 'none';
   document.getElementById('dashboard-container').style.display = 'block';
   document.getElementById('currentUser').textContent = currentUser.name || '-';
+  // Always start with status panel hidden (guards against stale display value on re-login)
+  const sp = document.getElementById('status-panel');
+  sp.style.display = 'none';
+  sp.innerHTML = '';
   document.getElementById('admin-controls').style.display = isAdmin ? 'flex' : 'none';
 }