USDZExporter: Add ar and includeAnchoringProperties options

Author: vincentfretin

types/three/examples/jsm/exporters/USDZExporter.d.ts

@@ -1,6 +1,8 @@
 import { Object3D } from "three";
 
 export interface USDZExporterOptions {
+    ar?: { anchoring: { type: 'plane' }, planeAnchoring: { alignment: 'horizontal' | 'vertical' | 'any' } };
+    includeAnchoringProperties?: boolean;
     quickLookCompatible?: boolean;
     maxTextureSize?: number;
 }