tailscale-vast-broker

  POST /v1/join         mint a container auth key   (bootstrap secret)
  POST /v1/heartbeat    refresh a container record  (bootstrap secret)
  GET  /v1/registry     live node -> VIP map        (gateway token)
  GET  /v1/bootstrap.sh container installer         (public)
  GET  /v1/onstart      vast.ai on-start snippet    (public)
  GET  /admin           roster and controls         (Cloudflare Access)