Review follow-up (Sara, fast-follow): the t no-active-region guard and the
draw-cue arm/disarm rule lived inline in the page with no direct coverage.
Extracted to pure resolveTrainingMark() (no-op when no region; recognition
enrolled flip) and canArmDraw()/shouldDisarmDraw(), each with unit tests
(10 cases total). The page now arms the draw cue only via canArmDraw and
disarms via shouldDisarmDraw, and routes t through resolveTrainingMark.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
