SunbeamClient accessors are now async and resolve auth per-client:
- SSO bearer (get_token) for admin APIs, Matrix, La Suite, OpenSearch
- Gitea PAT (get_gitea_token) for VCS
- None for Prometheus, Loki, S3, LiveKit
Fixes client URLs to match deployed routes: hydra→hydra.{domain},
matrix→messages.{domain}, grafana→metrics.{domain},
prometheus→systemmetrics.{domain}, loki→systemlogs.{domain}.
Removes all ad-hoc token helpers from CLI modules (matrix_with_token,
os_client, people_client, etc). Every dispatch just calls
client.service().await?.
