chore(world): add temporary diagnostics for porte strip, octree, ctx loss

src/hooks/three/useOctreeGraphNode.ts

@@ -1,9 +1,29 @@
 import { useEffect, useRef } from "react";
 import type { RefObject } from "react";
-import type { Object3D } from "three";
+import { Mesh, type Object3D } from "three";
 import { Octree } from "three-stdlib";
 import type { OctreeReadyHandler } from "@/types/three/three";
 
+// [diag] temporary — count meshes/triangles captured in the octree graph node
+function snapshotGraphNode(node: Object3D): {
+  meshCount: number;
+  triCount: number;
+} {
+  let meshCount = 0;
+  let triCount = 0;
+  node.traverse((obj) => {
+    if (obj instanceof Mesh) {
+      meshCount += 1;
+      const geom = obj.geometry;
+      const idx = geom.index;
+      triCount += idx
+        ? idx.count / 3
+        : (geom.attributes.position?.count ?? 0) / 3;
+    }
+  });
+  return { meshCount, triCount };
+}
+
 export function useOctreeGraphNode(
   graphNodeRef: RefObject<Object3D | null>,
   onOctreeReady: OctreeReadyHandler,
@@ -28,6 +48,15 @@ export function useOctreeGraphNode(
     const octree = new Octree();
     octree.fromGraphNode(graphNode);
 
+    // [diag] temporary — log octree contents to detect partial builds
+    const snapshot = snapshotGraphNode(graphNode);
+    console.log("[octree:build]", {
+      rebuildKey,
+      meshCount: snapshot.meshCount,
+      triCount: Math.round(snapshot.triCount),
+      timestamp: performance.now().toFixed(0),
+    });
+
     onOctreeReady(octree);
   }, [enabled, graphNodeRef, onOctreeReady, rebuildKey]);
 }