CameraHelper: Fix usage with WebGPU.

[AlaricBaraou]

Description

When using the WebGPURenderer the cameraHelper would show the wrong near.

You can see how the near plane change in the camera demo between WebGLRenderer and WebGPURenderer

Before

beforeFixCameraHelper.mp4

After

fixCameraHelper.mp4

This PR also add the camera example in its WebGPURenderer version ( used to test the helper )
If you prefer without the example I can remove it.
Also please confirm that I added / edited the correct files to add an example, it's my first.

This contribution is funded by Alaric Baraou💶

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	339.21 79.01	339.21 79.01	+0 B +0 B
WebGPU	486.27 134.93	486.27 134.93	+0 B +0 B
WebGPU Nodes	485.74 134.83	485.74 134.83	+0 B +0 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	465.1 112.07	465.1 112.07	+0 B +0 B
WebGPU	555.42 150.35	555.42 150.35	+0 B +0 B
WebGPU Nodes	511.34 140.12	511.34 140.12	+0 B +0 B