TSL: Add samplerComparison

[sunag]

Closes: #30685

Description

Add TSL samplerComparison function.

const shaderParams = {
	shadowDepthTexture: texture( directionalLight.shadow.map.depthTexture ),
	shadowDepthSampler: samplerComparison( directionalLight.shadow.map.depthTexture )
};
    
const fragmentShader = wgslFn(`
	fn main_fragment(
		shadowDepthSampler: sampler_comparison,
		shadowDepthTexture: texture_depth_2d
	) -> vec4<f32> {

		return vec4f( textureSampleCompare( shadowDepthTexture, shadowDepthSampler, vec2<f32>( 0.0 ), 5. ) );

	}
`);

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	336.02 78.26	336.02 78.26	+0 B +0 B
WebGPU	520.52 145.15	520.83 145.19	+304 B +49 B
WebGPU Nodes	519.99 145.04	520.29 145.09	+304 B +49 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	465.06 112.14	465.06 112.14	+0 B +0 B
WebGPU	591.01 160.79	591.14 160.82	+138 B +34 B
WebGPU Nodes	546.13 150.23	546.27 150.26	+138 B +34 B

[Spiri0]

I still think too rarely about new nodes. I find the solution elegant because it includes the name of the wgsl functionality. This makes its purpose immediately apparent.