fix: auto-reload all PWA windows when new SW activates

Chain activate: clear old caches → claim clients → navigate all windows.
client.navigate(url) forces a full reload so users always get the new
version without manually closing/reopening the PWA.
Also removed sw.js from PRECACHE (browser fetches SW directly, no need to cache it).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

sw.js

@@ -1,5 +1,5 @@
-const CACHE = 'ns-v22';
-const PRECACHE = ['/', 'index.html', 'styles.css', 'app.js', 'sw.js', 'manifest.json', 'icon.svg'];
+const CACHE = 'ns-v23';
+const PRECACHE = ['/', 'index.html', 'styles.css', 'app.js', 'manifest.json', 'icon.svg'];
 const SKIP_URLS = ['/rest/stream', '/rest/download', '/config.js'];
 
 self.addEventListener('install', e => {
@@ -9,11 +9,12 @@ self.addEventListener('install', e => {
 
 self.addEventListener('activate', e => {
   e.waitUntil(
-    caches.keys().then(keys =>
-      Promise.all(keys.filter(k => k !== CACHE).map(k => caches.delete(k)))
-    )
+    caches.keys()
+      .then(keys => Promise.all(keys.filter(k => k !== CACHE).map(k => caches.delete(k))))
+      .then(() => self.clients.claim())
+      .then(() => self.clients.matchAll({type: 'window', includeUncontrolled: true}))
+      .then(clients => clients.forEach(c => c.navigate(c.url)))
   );
-  self.clients.claim();
 });
 
 self.addEventListener('fetch', e => {