- Implement pure logic engine for tile management, shanten calculation, claim resolution, and faan scoring.
- Add heuristic AI (5 skill levels) using shanten minimization, ukeire tiebreaking, and adaptive defense.
- Build Phaser UI with tile rendering, dynamic scoreboard, claim prompts, hand-end modals, and a scoring reference panel.
- Integrate into frontend routing, opponent selection, and backend registry.
- Include headless verification script for tile catalog, scoring fixtures, and AI self-play invariant checks.
- Update game icon assets and add in-game tutorial.
