C3 experimental webgpu compatabilty

I have updated the addon to support the C3 webgpu experimental mode.

See more details about webgpu mode here: https://www.construct.net/en/make-games/releases/beta/r337 (you actually need to use r338, which has an additional bugfix for webgpu with 3D. At the time of this post, you also need the canary version of chrome and you also need to enable webgpu in chrome, google around for instructions.)

If you see an issue like the below, try changing the Project property Display->Sampling to trilinear, nearest, bilinear.

Same issue happens for 3DShape and I filed a bug: https://github.com/Scirra/Construct-bugs/issues/6943

So far, I do not seen an improvement in terms of performance for 3DObject (or 3DShapes). However, there is a change which may allow for performant changing of each face color, which could help with some simple, flat lighting per face (in the webgpu design, r,g,b,a color is passed through as a vertex, rather than as a uniform).