Windows discovery tool / windows (push) Successful in 1m35s
On the first real dispatch the proxy froze about 4.5 minutes in: pushall was published at QoS 1 from two tasks while holding the fleet lock, and once the in-flight window filled every publish blocked forever, stalling telemetry, heartbeats and the uplink. Publishes now time out after 10 s and pushall is QoS 0. Also adds an optional ams_slot to start_print so a job can choose its AMS slot (single-filament projects, same material type only).