fix: Update modal now properly detects when update completes

The update progress modal was stuck showing 'initializing' even after the
backend restarted and websocket reconnected. Users could see the connection
status badge reconnecting behind the modal, but the modal never cleared.

Now the modal:
- Watches websocket connection status during update
- Detects when backend disconnects and reconnects
- Verifies health after reconnection
- Automatically reloads the page when update is complete
- Shows clearer messaging about restart progress

frontend-modern/src/components/UpdateBanner.tsx

@@ -1,12 +1,14 @@
-import { Show, createSignal, createEffect, For } from 'solid-js';
+import { Show, createSignal, createEffect, For, useContext } from 'solid-js';
 import { useNavigate } from '@solidjs/router';
 import { updateStore } from '@/stores/updates';
 import { UpdatesAPI, type UpdatePlan } from '@/api/updates';
 import { UpdateConfirmationModal } from './UpdateConfirmationModal';
 import { UpdateProgressModal } from './UpdateProgressModal';
+import { WebSocketContext } from '@/App';
 
 export function UpdateBanner() {
   const navigate = useNavigate();
+  const wsContext = useContext(WebSocketContext);
   const [isExpanded, setIsExpanded] = createSignal(false);
   const [updatePlan, setUpdatePlan] = createSignal<UpdatePlan | null>(null);
   const [showConfirmModal, setShowConfirmModal] = createSignal(false);
@@ -300,6 +302,8 @@ export function UpdateBanner() {
           setShowProgressModal(false);
           navigate('/settings/updates');
         }}
+        connected={wsContext?.connected}
+        reconnecting={wsContext?.reconnecting}
       />
     </Show>
   );

frontend-modern/src/components/UpdateProgressModal.tsx

@@ -1,10 +1,12 @@
-import { createSignal, Show, onMount, onCleanup } from 'solid-js';
+import { createSignal, Show, onMount, onCleanup, createEffect } from 'solid-js';
 import { UpdatesAPI, type UpdateStatus } from '@/api/updates';
 
 interface UpdateProgressModalProps {
   isOpen: boolean;
   onClose: () => void;
   onViewHistory: () => void;
+  connected?: () => boolean;
+  reconnecting?: () => boolean;
 }
 
 export function UpdateProgressModal(props: UpdateProgressModalProps) {
@@ -12,6 +14,7 @@ export function UpdateProgressModal(props: UpdateProgressModalProps) {
   const [isComplete, setIsComplete] = createSignal(false);
   const [hasError, setHasError] = createSignal(false);
   const [isRestarting, setIsRestarting] = createSignal(false);
+  const [wsDisconnected, setWsDisconnected] = createSignal(false);
   let pollInterval: number | undefined;
   let healthCheckTimer: number | undefined;
   let healthCheckAttempts = 0;
@@ -113,6 +116,36 @@ export function UpdateProgressModal(props: UpdateProgressModalProps) {
     healthCheckTimer = window.setTimeout(checkHealth, 0);
   };
 
+  // Watch websocket status during restart
+  createEffect(() => {
+    if (!isRestarting()) return;
+
+    const connected = props.connected?.();
+    const reconnecting = props.reconnecting?.();
+
+    // Track if websocket disconnected during restart
+    if (connected === false && !reconnecting) {
+      setWsDisconnected(true);
+    }
+
+    // If websocket reconnected after being disconnected, the backend is likely back
+    if (wsDisconnected() && connected === true && !reconnecting) {
+      console.log('WebSocket reconnected after restart, verifying health...');
+      // Give it a moment for the backend to fully initialize
+      setTimeout(async () => {
+        try {
+          const response = await fetch('/api/health', { cache: 'no-store' });
+          if (response.ok) {
+            console.log('Backend healthy after websocket reconnect, reloading...');
+            window.location.reload();
+          }
+        } catch (error) {
+          console.warn('Health check failed after websocket reconnect, will keep trying');
+        }
+      }, 1000);
+    }
+  });
+
   onMount(() => {
     if (props.isOpen) {
       // Start polling immediately
@@ -252,7 +285,11 @@ export function UpdateProgressModal(props: UpdateProgressModalProps) {
                       <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z" />
                     </svg>
                     <div class="text-sm text-blue-800 dark:text-blue-200">
-                      Pulse is restarting with the new version. This page will reload automatically when ready.
+                      <Show when={wsDisconnected()} fallback={
+                        <span>Pulse is restarting with the new version...</span>
+                      }>
+                        <span>Waiting for Pulse to complete restart. This page will reload automatically.</span>
+                      </Show>
                     </div>
                   </div>
                 </div>