A hard gateway crash (exit code 1) skips the graceful shutdown path, so
sessions.json is never cleared and is left pointing at sessions already
ended in state.db. On the next startup get_or_create_session() reuses
those stale entries as long as the time/policy reset checks pass — it
never consults end_reason — so every incoming message is silently routed
into a closed session, with no log or error (#52804).
SessionStore._ensure_loaded_locked() now calls a new
_prune_stale_sessions_locked() that drops any entry whose session_id has
end_reason IS NOT NULL in state.db. Idempotent, _db=None / legacy-absent
safe, DB errors non-fatal, sessions.json rewritten only when something
was pruned. Self-heals into a fresh session on the next message.
Reported and diagnosed by @terry197913 (#52808).
