When the game gives up on a join (game mode timed out, or it
disconnected), a join still queued isn't sent anymore, and the rest of
the server's answer to one already sent is dropped: its players, and the
BSSID that came last and connected us. Players joining a group we've
just left (before the server knew) are dropped too, instead of staying
in our peer list.
Replaces the previous fix, which only dropped a late BSSID: on Windows
the join itself was still queued when game mode timed out in
net/adhoc/gamemode, and went out after it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>