Initial checkin

public/sw.js

@@ -0,0 +1,33 @@
+// sw.js — service worker for the notification + push test page.
+
+self.addEventListener('install', () => self.skipWaiting());
+self.addEventListener('activate', (event) => event.waitUntil(self.clients.claim()));
+
+// Server-sent push lands here even when every tab is closed.
+self.addEventListener('push', (event) => {
+  const data = event.data ? event.data.json() : {};
+  event.waitUntil(
+    self.registration.showNotification(data.title || 'Push', {
+      body: data.body || '',
+      icon: 'https://dummyimage.com/192x192/47a/fff.png&text=%E2%86%93',
+      vibrate: [120, 60, 120],
+      tag: 'push'
+    })
+  );
+});
+
+// Handle taps on the notification or its action buttons.
+self.addEventListener('notificationclick', (event) => {
+  const action = event.action; // '', 'open', or 'dismiss'
+  event.notification.close();
+  if (action === 'dismiss') return;
+
+  event.waitUntil(
+    self.clients.matchAll({ type: 'window', includeUncontrolled: true }).then((windows) => {
+      for (const win of windows) {
+        if ('focus' in win) return win.focus();
+      }
+      if (self.clients.openWindow) return self.clients.openWindow('/');
+    })
+  );
+});