SplatPager: null texture source to ensure underlying arrays can be GC'ed (#326)

Co-authored-by: Aleksandr Korotaev <lekzd@mail.ru>

Author: mrxz

src/SplatPager.ts

@@ -827,32 +827,41 @@ export class SplatPager {
     this.numFetchers = 0;
 
     this.packedTexture.value.dispose();
+    this.packedTexture.value.source.data = null;
     if (this.extTexture.value !== SplatPager.emptyExtTexture) {
       this.extTexture.value.dispose();
+      this.extTexture.value.source.data = null;
     }
 
     if (!this.extSplats) {
       if (this.sh1Texture.value !== SplatPager.emptySh1Texture) {
         this.sh1Texture.value.dispose();
+        this.sh1Texture.value.source.data = null;
       }
       if (this.sh2Texture.value !== SplatPager.emptySh2Texture) {
         this.sh2Texture.value.dispose();
+        this.sh2Texture.value.source.data = null;
       }
       if (this.sh3Texture.value !== SplatPager.emptySh3Texture) {
         this.sh3Texture.value.dispose();
+        this.sh3Texture.value.source.data = null;
       }
     } else {
       if (this.sh1Texture.value !== SplatPager.emptyExtSh1Texture) {
         this.sh1Texture.value.dispose();
+        this.sh1Texture.value.source.data = null;
       }
       if (this.sh2Texture.value !== SplatPager.emptyExtSh2Texture) {
         this.sh2Texture.value.dispose();
+        this.sh2Texture.value.source.data = null;
       }
       if (this.sh3Texture.value !== SplatPager.emptyExtSh3Texture) {
         this.sh3Texture.value.dispose();
+        this.sh3Texture.value.source.data = null;
       }
       if (this.sh3TextureB.value !== SplatPager.emptyExtSh3BTexture) {
         this.sh3TextureB.value.dispose();
+        this.sh3TextureB.value.source.data = null;
       }
     }
   }