Update frontend assets, enhance idle animation, and adjust layout

fix: update Sune algorithm prompt and expected moves in practice drills

feat: implement practice drills subsystem with evaluation and UI panel

Fix coaching bug on mistake detection and alignment on expected moves

feat: implement coaching messages for lesson steps

feat: implement lesson engine and progress tracking for Rubik's Cube lessons

feat: redesign UI with new CSS styles and debugger panel enhancements

feat: add comprehensive tests for drag controls and cube state management

feat: add unit tests for MoveAnimator and Cubelet functionality

Cut iframe, still janky on scramble

Placeholder Rubics Cube on Gradio