The act_runner on the QNAP creates an ephemeral docker bridge per job.
That network can't always reach the canonical PORTAINER_URL
(http://192.168.1.30:9000) — first deploy run failed with
'Failed to connect to 192.168.1.30 port 9000 after 130317 ms'.
New step 0 probes several candidate URLs (container's own IPs, default
gateways, then the secret value as fallback) against /api/status and
uses the first one that returns 200. The reachable host is then reused
for the DELETE+CREATE calls and the smoke-test on :3001.
root