feat: Implement Phaser 3.90 framework with player movement, parallax backgrounds, mouse reticle, and sound effects
- Replaced old Player class with new ES6 module-based implementation using A/D keys for movement
- Added parallax background scrolling with multiple layers
- Implemented mouse reticle with glow effect instead of default cursor
- Integrated audio assets for game sounds and background music
- Updated game configuration to 600x800 resolution with FIT scaling
- Enhanced shooting mechanics with angle-based bullet trajectory calculation
- Improved UI elements including score text and game over screen
- Added enemy spawning and collision detection systems
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