The compose file published a second host port on the docker bridge IP so
sibling containers could reach the relay. That is a host-reachable address for
a service whose entire safety story is that it has exactly one, on loopback.
It joins the consumers' existing docker network instead, and is reached there
by name on the container port. Nothing about a consumer's deployment has to
change to use it, and the relay gains no address outside that network.
Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
