Follow-up to #12301.
The drain-timeout branch of _stop_impl() was iterating the drain-start
snapshot (active_agents) when marking sessions resume_pending. That
snapshot can include sessions that finished gracefully during the drain
window — marking them would give their next turn a stray
'your previous turn was interrupted by a gateway restart' system note
even though the prior turn actually completed cleanly.
Iterate self._running_agents at timeout time instead, mirroring
_interrupt_running_agents() exactly:
- only sessions still blocking the shutdown get marked
- pending sentinels (AIAgent construction not yet complete) are skipped
Changes:
- gateway/run.py: swap active_agents.keys() for filtered
self._running_agents.items() iteration in the drain-timeout mark loop.
- tests/gateway/test_restart_resume_pending.py: two regression tests —
finisher-during-drain not marked, pending sentinel not marked.