Stage 0: manifest gains id "/" (what Chrome already derives from start_url), scope, a 512 maskable
icon, and drops the portrait lock. The service worker keeps the session ({baseUrl, accessToken}) in
IndexedDB `ratatoskr-sw` so a push can wake a worker with no tab; the page's existing logout message
deletes it.
Stage 1: `push` and `notificationclick` handlers (src/app/features/push), a pusher toggle in
notification settings, `push` block in config.json shipped empty (off). Tested against a mock
homeserver and Matrix gateway body.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>