matrix_user_uid/gid, matrix_server_fqn_matrix, matrix_addons_container_network
are all defined by custom/matrix-base and required by livekit_server role.

https://claude.ai/code/session_01SbRgWsRDKpTZ2TTbWDhtEB

- Revert setup.yml to use galaxy/livekit_server (avoids loading all
  uninstalled galaxy roles when running with --tags)
- Add livekit.yml: minimal standalone playbook that only includes
  galaxy/systemd_docker_base and custom/livekit_server, so livekit
  setup can run independently without requiring all other galaxy roles

Usage:
  ansible-playbook -i inventory/hosts livekit.yml \
    --tags=setup-livekit-server,start-group-services

https://claude.ai/code/session_01SbRgWsRDKpTZ2TTbWDhtEB