Dev-only command that drives the planar base_motion joint in a circle,
publishing synthetic JointState messages carrying BB.Math.Transform2D
poses on [:sensor, :simulated] for ~3s at ~30Hz.
Its purpose is to demonstrate multi-DoF joints end-to-end: the joints
panel's read-only pla row tracks the pose, the event log renders the
compact (x, y, θ°) form, and the 3D view shows the whole arm driving
the loop. Mirrors Dev.StreamHandler's publish pattern; the burst runs
in the command's own process, returning the state machine to its initial
operational state when done.
Goal shape: none.