WebGPURenderer: Avoid using proxy in rendering cycle

[sunag]

Related issue: #29066 (comment)

Description

Proxy should be avoided in the rendering cycle as they harm performance.

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

Filesize dev	Filesize PR	Diff
685.1 kB (169.6 kB)	685.1 kB (169.6 kB)	+0 B

🌳 Bundle size after tree-shaking

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

Filesize dev	Filesize PR	Diff
462 kB (111.5 kB)	462 kB (111.5 kB)	+0 B

[0b5vr]

This PR improves the CPU load on WebGPURenderer!
It's still less performant compared to WebGLRenderer though, the bottleneck still comes from somewhere around NodeMaterial according to Chrome DevTools profiler.

[0b5vr]

about updateNode, it seems we are simply doing crazy amount of updateNode invocation for webgpu_performance.html.

I count the call of updateNode for each updateType per single renderAsync:

"render": 2397
"object": 10376
"frame": 6384

This is the content of nodeBuilder.updateNodes: