New decnet.agent.heartbeat asyncio loop wired into the agent FastAPI
lifespan. Every 30 s the worker POSTs executor.status() to the master's
/swarm/heartbeat with its DECNET_HOST_UUID for self-identity; the
existing agent mTLS bundle provides the client cert the master pins
against SwarmHost.client_cert_fingerprint.
start() is a silent no-op when identity env (HOST_UUID, MASTER_HOST) is
unset or the worker bundle is missing, so dev runs and un-enrolled hosts
don't crash the agent app. On non-204 responses the loop logs loudly but
keeps ticking — an operator may re-enrol mid-session, and fail-closed
pinning shouldn't be self-silencing.
anti
bf01804736