The prebuilt theta-agent-linux-amd64 was built before the v1.3.0 heartbeat_ack
fix, so the installed agent still logged 'Unknown command type: heartbeat_ack'.
Rebuild it with the fix; add a test asserting heartbeat_ack is silently ignored
(no response, no command, no log).
The server replies to the agent's own heartbeat with heartbeat_ack; the agent
had no case for it, so it fell through to the unknown-command handler, logged
'Unknown command type: heartbeat_ack' every minute, and answered with a spurious
error response. heartbeats are fire-and-forget acks — nothing to run, nothing to
reply.
wmantly