Release v0.2.0: GLTF Texture Support

Major Features:
- Full GLTF texture loading from embedded GLB files
- UV coordinate extraction and mapping
- Multi-mesh support (FlightHelmet: 6 meshes, 55K vertices, 94K triangles)
- Texture upload to WebGL (RGB/RGBA formats)
- Updated shader with texture sampling
- Depth testing and face culling for proper 3D rendering
- OpenGL state management (restore after rendering)

Improvements:
- FlightHelmet renders with full textures (2048x2048)
- Camera positioning optimized per model
- Proper alpha handling and blending control
- Safe deployment scripts (build-prod.ps1, gh-deploy.ps1)

Bug Fixes:
- Fixed GLTF loader to combine all meshes (not just first)
- Fixed rotation timing (start_time tracking)
- Fixed face culling state restoration for other samples