TSL: Introduce pointer | WGSL ptr support

[sunag]

Related issue: Closes #29401

Description

Introduces pointer support, below is an example of how to use it for storage buffers, although it has many other applications.

// buffer

const particleBuffer = new THREE.StorageInstancedBufferAttribute( particleNum, 2 );

// function

const getElement = wgslFn( `
fn main_vertex( vertexBuffer: ptr<storage, array<vec2<f32>>, read_write>, index: u32 ) -> vec2f {

	return vertexBuffer[ index ];

}
` );

// function call

const particle = getElement( particleBufferNode, instanceIndex );

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	688.13 170.5	688.13 170.5	+0 B +0 B
WebGPU	808.1 217.67	808.2 217.71	+99 B +47 B
WebGPU Nodes	807.61 217.53	807.71 217.58	+99 B +47 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	462.85 111.78	462.85 111.78	+0 B +0 B
WebGPU	536.53 144.8	536.63 144.86	+99 B +53 B
WebGPU Nodes	492.61 134.53	492.71 134.59	+99 B +53 B

[Spiri0]

As usual, your solution is much more elegant. More efficient and shorter.
I tested it straight away and it worked as expected