Review follow-ups on the salvage:
- The helper script's success check accepted any "PID" line, including
the "PID" = -1 a recently-crashed job reports — while the in-process
path's _parse_launchd_pid_from_list_output rejects non-positive PIDs.
Both bash sites now require a positive PID (grep -qE '"PID" = [0-9]+;')
so the two paths enforce the same supervised-PID standard.
- _graceful_restart_via_sigusr1's drain-wait tail was a duplicate of the
new _wait_for_pid_exit — now delegates to it.
- Stale comments: the ancestry-detection framing at the top of the reload
block, and the exhaustion log's '(refresh ran outside gateway process
tree)' which is false on the new helper-spawn-failure fallback path
(now '(in-process fallback path)').