Redesign the 640x480 UI from horizontal bottom-bar controls to a split-screen
layout that maximizes album art visibility for the child user. Buttons stack
vertically in a 200px left panel; artwork fills the remaining right panel at
up to 420x460. Volume removed from focus cycle in favor of dedicated keys
(+/-, volume buttons, shoulder buttons). Navigation changed to UP/DOWN.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>