Adds the LDAP outpost deployment and routes ports 389 and 636 on
gateway-internal to it. 636 is a TLS listener in Terminate mode so
cert-manager renews the LDAPS certificate automatically, and both
listeners forward to the outpost's plaintext 3389.
allowedRoutes.kinds is set explicitly on both listeners: a TCP listener
permits no route kinds by default and a TLS listener defaults to
TLSRoute, so the TCPRoute would not attach otherwise.