manifest.webmanifest with the existing icons, apple-touch-icon, and SW
registration at startup. The old sw.js was a self-unregistering cleanup
stub — meaning serviceWorker.ready never resolved and web push has been
silently dead; the new worker handles push display and notification
clicks, and makes the app installable.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
