NodeMaterial: Dynamically copy properties in copy()

[sunag]

Related issue: N/A

Description

This PR refactors NodeMaterial.copy() to dynamically copy properties instead of relying on a hardcoded list of node property assignments.

The new implementation ensures compatibility by verifying that a property is defined on both the source and the target before copying, also ignoring common properties like is*, uuid, id, and private properties.

Currently the code below does not work.

// A common use case

const mesh = gltf.scene.children[ 0 ];

const nodeMaterial = new THREE.MeshStandardNodeMaterial();
nodeMaterial.copy( mesh.material ); // copy from MeshStandardMaterial

mesh.material = nodeMaterial;

The defaults values currently are defined procedurally, the PR #28328 improve this, but it's require major changes.

The copying process honors nested .copy() calls for properties that implement them (such as Color or Vector2), ensuring that sub-object values are properly copied instead of just overwriting references and additionally, it deep-copies userData and clones individual elements inside the clippingPlanes array.

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	365.48 86.82	365.48 86.82	+0 B +0 B
WebGPU	666.43 184.37	664.42 184.1	-2.01 kB -267 B
WebGPU Nodes	664.47 184.06	662.47 183.8	-2.01 kB -264 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	507.44 123.35	507.44 123.35	+0 B +0 B
WebGPU	745.68 200.56	744.33 200.43	-1.35 kB -135 B
WebGPU Nodes	694.9 188	694.65 188.02	-249 B +17 B

[sunag]

/cc @brunosimon