AnimationClip: Deprecate parseAnimation().

[Mugen87]

Related issue: -

Description

The static method AnimationClip.parseAnimation() was intended to parse animations of the old JSON format used by JSONLoader. The method has no other use in the library, AFAICS.

I vote to deprecate it now so we can safely remove it at the end of the year.

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	336.16 78.31	336.16 78.31	+0 B +0 B
WebGPU	522.64 145.1	522.64 145.1	+0 B +0 B
WebGPU Nodes	522.11 145	522.11 145	+0 B +0 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	465.27 112.2	465.27 112.2	+0 B +0 B
WebGPU	593.11 160.72	593.11 160.72	+0 B +0 B
WebGPU Nodes	548.23 150.16	548.23 150.16	+0 B +0 B