Figure out exact color space support

[lgarron]

• What color space do we define colors in?
• How do we get SVG colors to match 3D colors?
• How do we handle sprites?
• Can we easily support HDR?

This might also be a good time to look at unifying colors: #171

[lgarron]

• Can we easily support HDR?

We can now!

• Examples: Add WebGPU HDR Example mrdoob/three.js#31893
• https://threejs.org/examples/webgpu_hdr.html