Three.js integration for gg-web-engine, providing 3D rendering

Installation:

1. make sure @gg-web-engine/core installed
2. npm install --save @gg-web-engine/three

The package brings three (with @types/three) as its own dependency, pinned to the exact version it is built and tested against, so nothing else needs installing. If your app also imports it directly, use that same version, so the bundle carries only one copy.

Addons are not included in three.js build, but @gg-web-engine/three provides GLTFLoader:

import { GLTFLoader } from '@gg-web-engine/three';