feat: #4 shift lights + #5 phone dash + #6 PWA support

static/sw.js

@@ -0,0 +1,3 @@
+self.addEventListener('install', (e) => { self.skipWaiting(); });
+self.addEventListener('activate', (e) => { e.waitUntil(clients.claim()); });
+self.addEventListener('fetch', (e) => { e.respondWith(fetch(e.request).catch(() => caches.match(e.request))); });