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>
- bitECS world with time tracking (delta, elapsed, tick)
- 5 components: Position, Velocity, SpriteRef, Health, ChemicalComposition
- Movement system (velocity * delta) + bounce system (boundary reflection)
- Health system with damage, healing, death detection
- Entity factory (createGameEntity/removeGameEntity)
- Phaser bridge: polling sync creates/destroys/updates circle sprites
- GameScene: 20 colored circles bouncing at 60fps
- BootScene: click-to-start transition, version bump to v0.2.0
- 39 ECS unit tests passing (74 total)
Co-authored-by: Cursor <cursoragent@cursor.com>
