Promote the illumination panel's __main__ self-check to a real pytest
file so CI counts it, add busy-overlay render checks (status text
paints, video view routes through it), and cover the motor group's
incomplete-entry and below-min Enter paths. Local diff coverage from
the gui suite alone: 82 percent.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>