Holds one axis at a fraction of its described velocity. action is begin, update or end. Needs an armed session. GET /dense-execution/jog/state returns the current state.

Send begin, then update every 50 ms while the operator holds the control, then end. An update may not change axis, direction or fraction; end the hold and begin a new one. Each update lives for the cell's jog input age (250 ms on a LAN cell). If updates stop, the jog ends with jog_input_deadline_expired and the axis ramps to a hold.

Errors (409 unless noted): jog_session_stale, jog_mode_conflict (a move, a program or another hold is active), no_grant, jog_not_ready, invalid_axis_mask, 400 jog_invalid_vector, jog_input_deadline_expired, jog_transport_congested, dense_target_unavailable, and native jog reasons.