align structure more with underlying chunk layout

src/models/data/data-tracker-xyz-chunk.ts

@@ -0,0 +1,12 @@
+import { Chunk } from '../chunk';
+
+export interface DataTrackerXYZChunkData {
+  x: number;
+  y: number;
+  z: number;
+}
+
+export interface DataTrackerXYZChunk {
+  chunk: Chunk;
+  data: DataTrackerXYZChunkData;
+}