Renderer: Introduce colorBufferType.

[Mugen87]

Related issue: #30387, #30392

Description

This PR introduces a new renderer parameter that allows to define the type of color buffers. By default, THREE.HalfFloatType is used which results in 64bit color buffers. To improve performance in use cases with limited memory or bandwidth, THREE.UnsignedByteType might be used which results in 32bit color buffers.

This change feels indeed better than #30392 which relied on a questionable automatism. The new parameter makes the configuration more explicit.

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	336.27 78.29	336.27 78.29	+0 B +0 B
WebGPU	516.75 143.47	516.99 143.53	+234 B +61 B
WebGPU Nodes	516.22 143.36	516.45 143.42	+234 B +63 B

🌳 Bundle size after tree-shaking

Minimal build including a renderer, camera, empty scene, and dependencies.

	Before	After	Diff
WebGL	465.25 112.13	465.25 112.13	+0 B +0 B
WebGPU	588.76 159.63	588.99 159.69	+234 B +58 B
WebGPU Nodes	544.14 149.2	544.38 149.25	+234 B +56 B