- Attempt reconnection on 'disconnected' | 'failed' | 'closed' states (BaseWebRTC)
- Relax gating: rejoin when roomId exists and any of isPeerDisconnected, isSocketDisconnected, or socketId changed
- Auto re-join room on socket 'connect' if lastJoinedSocketId differs or not in room; send initiator-online for initiators
- Track lastJoinedSocketId after successful join and reset isInRoom when socketId changes to bypass early-return
- Update flows to document mobile background/foreground reconnection and socketId-based rejoin