sidecamp-v0.23.6

fix(sidecamp): source the chat contact list from the chat registry

The Chat tab's recipient dropdown was built from networkPeers
(GET /api/peers), which only lists peer-daemon sessions on /ws/peer.
Users chatting from the TuneCamp webapp connect to /ws/chat and never
appear there, so they were invisible from Sidecamp while Sidecamp users
were visible to them.

Add getChatPeers (GET /api/chat/peers — the registry both transports
write to) to the Electron network provider and the Capacitor adapter,
and poll it every 5s while the Chat tab is open.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>