1272b81cee
Page-level Notifications can't fire when a tab is frozen/closed (and never on mobile), which is why recipients on another tab/app got nothing. Adds a notification-only service worker (sw.js, no caching) + Web Push: - push.js: optional web-push wrapper (no-op unless web-push installed AND VAPID_PUBLIC_KEY/VAPID_PRIVATE_KEY set -> app unaffected if unconfigured). - push_subscriptions table + R.pushSubs repo (upsert by endpoint, prune dead). - /api/push/vapid|subscribe|unsubscribe; DM + group message routes also send a Web Push to recipients. - Client registers /sw.js, subscribes when permission granted; hidden-tab popups are left to push to avoid double-notifying (pushActive flag); SW suppresses the OS popup when a tab is visible. Removes the old code that unregistered SWs. Requires (prod, once): npm install + VAPID_PUBLIC_KEY/VAPID_PRIVATE_KEY/VAPID_SUBJECT env. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>