v0.0.1 Camera Integration

v0.0.1: OpenGL ES rendering engine and camera integration

- Migrated from Filament to OpenGL ES 3.0 for Gaussian splat rendering with modern VAOs/UBOs
- Added CameraX camera preview with permission handling in viewer screen
- Simplified axis widget with gesture-triggered updates for performance
- Enhanced camera controller with target positioning and dynamic far plane
- Added unit tests for camera and viewer functionality
- Removed Filament dependencies and updated build configurations