Adds the register entry for Zigbee2MQTT (same ACL as the legacy user
zigbee2mqtt, different name so it cannot shadow the running password login)
and its Secret to the controller's revocation list. Nothing restarts; the
controller picks the register up live and issues mqtt-zigbee2mqtt-bridge-tls
before the Z2M switch lands.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>