7e46d1ed1d
UIScene renders as overlay on top of GameScene: - Health bar (top-left) with color transitions green→yellow→red - 4 quick slots (bottom-center) with active highlight, item symbols and counts - Inventory weight/slots info (bottom-right) - Controls hint (top-right) GameScene pushes state to Phaser registry each frame. Phase 4 (Player Systems) complete — 222 tests passing. Co-authored-by: Cursor <cursoragent@cursor.com>