- Server-side participant dedup on join: remove ghost entries with same name but different ID
- Reduce stale participant threshold from 1hr to 15min to match client-side cleanup
- Refactor push subscriptions from Set to Map keyed by endpoint (prevents duplicate pushes)
- Store participantId with push subscriptions for identity-aware routing
- Exclude joining user from their own "Friend Joined" push notification
- Callout (ping) sends visible push to offline users ("X is looking for you!") instead of silent push
- Return last known locations in callout API response for immediate display
- Service worker: 10s cooldown on location request pushes to prevent burst on app reopen
- Service worker: suppress join/leave notifications when app window is focused
- Pass callerName from ParticipantList so offline callout shows who's looking
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Jeff Emmett