Speed up baked stable animations

[agustin-littlehat]

Summary

• make baked stable animation use typed triangle-frame updates by default when the mesh is eligible
• preserve baked solid texture colors on the optimized animation path
• keep React, Vue, vanilla, and website stable-triangle color cadence aligned
• keep the animated-human and non-voxel drag trace benches for verification

Verification

• pnpm test && pnpm build