When a client reconnects with the same session_id before the 90s
stale sweeper runs, the old ghost presence stays in the connections
map. Result: duplicate entries in list_peers for the same Claude
Code instance.
Now: handleHello iterates connections for matching (meshId, sessionId),
closes the old WS, deletes from map, marks disconnected in DB.
One session_id = one presence, always.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>