WebGPURenderer: Introduce ShadowNode (mrdoob#29567)

* introduce shadow node

* undo test setting

* lost in merging

* cleanup

---------

Co-authored-by: aardgoose <[email protected]>

Author: aardgoose

src/nodes/Nodes.js

@@ -131,6 +131,7 @@ export { default as BasicEnvironmentNode } from './lighting/BasicEnvironmentNode
 export { default as IrradianceNode } from './lighting/IrradianceNode.js';
 export { default as AONode } from './lighting/AONode.js';
 export { default as AnalyticLightNode } from './lighting/AnalyticLightNode.js';
+export { default as ShadowNode } from './lighting/ShadowNode.js';
 
 // pmrem
 export { default as PMREMNode } from './pmrem/PMREMNode.js';

src/nodes/TSL.js

@@ -130,6 +130,7 @@ export * from './gpgpu/AtomicFunctionNode.js';
 export * from './accessors/Lights.js';
 export * from './lighting/LightsNode.js';
 export * from './lighting/LightingContextNode.js';
+export * from './lighting/ShadowNode.js';
 
 // pmrem
 export * from './pmrem/PMREMNode.js';