LOD: Add removeLevel().

[JaimeTorrealba]

Related issue: #29074

closes #29074

Description

Add the method removeLevel to LOD class

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	685.42 169.7	685.42 169.7	+0 B +0 B
WebGPU	828.13 222.15	828.13 222.15	+0 B +0 B
WebGPU Nodes	827.71 222.05	827.71 222.05	+0 B +0 B

🌳 Bundle size after tree-shaking

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

	Before	After	Diff
WebGL	462.02 111.48	462.02 111.48	+0 B +0 B
WebGPU	526.16 141.85	526.16 141.85	+0 B +0 B
WebGPU Nodes	482.82 131.66	482.82 131.66	+0 B +0 B