chore: Tracking - UX drag-and-drop and canvas visuals

[spenceriam]

Tracking: UX drag-and-drop and canvas visuals\n\n- [ ] #41 Drag-drop: component does not drop on mouseup\n- [ ] #42 Pin points visible during drag; hide while moving/placing\n- [ ] #43 Remove red canvas border (debug viewport outline)\n- [ ] #44 Arduino board shows square artifact when placed\n- [ ] #45 Esc cancels active drag or new placement\n