Review round 5 (planner-reviewer-codex-01, NOT PASS at 2b1d590):
- F1 bounded lock cycle: the stopper holds the per-job lifecycle lock while
it waits for the timer to exit, and the timer's exit cleanup waited for
that same lock, so every stop ran out the drain and ended in SIGKILL with
a false "did not drain" warning. The exiting timer now tries the lock
without blocking (lifecycle_lock(blocking=False)); when it is busy the
ownership operation holding it removes the pidfile, and when it is free
the own-pid comparison is kept.
- F2 untracked owner: when writing the new timer's pid fails after the
spawn, _spawn_timer_locked kills and reaps that exact process while the
lock is still held and drops only a partial pidfile of that attempt,
then re-raises.
- tests: an idle timer stops well before a 10 s drain without SIGKILL;
a pidfile failure after spawn leaves no survivor, no pidfile and a free
lock (both fail on 2b1d590); a spawn failure leaves nothing behind and
the next start works.
- docs: MESSAGING 2.5 and VERSIONS item 1 describe the lifecycle lock;
VERSIONS test count 31.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HCGpJXhSZasJLU38ksDghe