ensureGroupChatSession's resume loop caught ANY session.resume error
(stored sid, then title lookup) identically and fell through to
session.create — the same bug findExistingCanonicalChat was fixed for
hours earlier (87b645f52c) in the same file: a transient failure (the
backend still warming up after a restart, a network blip on a
cross-connection lookup, an oversized-resume refusal) read as "no
session, mint a new one". That forks the member's real session AND
silently overwrites room.sessions[key], making the original
unreachable from the room. ensureGroupChatSession is actually more
exposed than the 1:1 case: it runs every group turn
(runGroupChatMemberTurn), with two independent swallow points.
Distinguish "genuinely doesn't exist" from "transient failure" the
same way the gateway itself does: session.resume's own handler
(tui_gateway/methods_session.py) returns JSON-RPC code 4007 only when
the target truly isn't found; every other failure (including 4130,
"session too large to resume" — a session that DOES exist) now
surfaces instead of being silently swallowed. The existing outer
try/catch at the call site already treats a thrown error as "this
member passes the round" (recordGroupActivity kind: 'failed'), so
nothing new needs to catch it — a transient hiccup now costs one
skipped round instead of a permanent fork.
pierrenode
525597c9c3