- Added new sound effect and music MP3 files to the project.
- Updated **BootScene** to preload all music tracks and sound effects.
- Implemented music playback:
* MenuScene now plays looping title music and stops it on shutdown.
* GameScene now stops any playing music on shutdown and starts level‑specific background music with fallback to the last track.
- Added SFX triggers for player shooting, alien shooting, missile launch, impacts, alien death, and player death.
- Cleaned up formatting and minor code style issues in GameScene (group/array declarations, tweens, UI text creation, level setup loops, etc.).
- Ensured proper cleanup of music objects when scenes change.
- New alien types (basic, spread, missile) with distinct speed, fire‑rate, explosion colors and textures.
- Implement spread‑shot pattern and homing‑missile behavior with steering logic.
- Asteroid constructor now accepts a speed multiplier; level speed increases each level.
- Extend Bullet to support homing missiles (new texture, lifetime, turn rate, steering).
- Introduce CRTPipeline post‑FX (barrel distortion, scanlines, vignette) and register it in the game config.
- Apply CRT pipeline to GameScene and MenuScene.
- Add custom reticle cursor graphics (rotating outer/inner layers).
- Update BootScene to generate textures for new alien types and reticle.
- Implement `AlienShip.explode()` with cyan flash, shrinking spin animation and a shockwave ring.
- Enhance `Player.die()` to flash white, hide the sprite, and spawn shattering shard graphics.
- Introduce `GameScene.spawnImpactSparks()` to create brief yellow spark particles on bullet impacts.
- Update bullet‑asteroid and bullet‑alien collision handling to trigger impact sparks and use the new alien explosion.
- Minor refactor to use the new visual effects for a more polished death sequence.
- Import and register new `BootScene` and `MenuScene` in `main.js`.
- Create `BootScene` to generate all shared textures once at startup and then start the menu.
- Implement full-featured `MenuScene` with background asteroids, wandering alien, title, controls panel, and start button (including ENTER key support).
- Remove texture generation logic and helper from `GameScene`; it now relies on textures created by `BootScene`.
- Change game‑over handling to return to the menu instead of restarting the game.
- Added `warpOut()` to `AlienShip` with spin‑shrink animation and black‑hole ring visual.
- Modified `spawnAlienBullet` to pass the firing ship to `Bullet`.
- Extended `Bullet` constructor with `ownerEntity` to store the originating `AlienShip`.
- Updated collision callbacks in `GameScene` to trigger `warpOut()` on the owning ship when its bullet hits the player or when the player collides with an alien, and to remove the ship from the alien list.
- Fixed overlap order for alien bullets vs. player.
These changes give alien ships a dramatic disappearance animation and ensure proper cleanup after collisions.