Codex regression gate found the launchd guard blocked ANY ctl.sh start while a
launchd job was live — including a legitimate second instance on a different
port (HERMES_WEBUI_PORT=8788). Now _launchd_webui_pid only treats the launchd
job as a conflict when its PID is actually listening on the requested CTL_PORT
(via a new best-effort _pid_listens_on_port helper using lsof); a different-port
start is allowed. When port ownership can't be determined (no lsof), falls back
to guarding only the default 8787 port so non-default ports are never wrongly
blocked. Adds a different-port-allowed regression test + makes the existing
block test deterministic. Co-authored-by preserved.