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

src/world/GameMapCollision.tsx

@@ -277,12 +277,22 @@ function CollisionModelInstance({
     // by MergedStaticMapModel and is unaffected.
     if (node.name !== "lafabrik") return;
 
+    // [diag] temporary — collect all door-like candidate names to debug stripping
+    const candidates: string[] = [];
     const removed: THREE.Object3D[] = [];
     sceneInstance.traverse((child) => {
+      if (/porte/i.test(child.name)) {
+        candidates.push(child.name);
+      }
       if (child.name === "porte") {
         removed.push(child);
       }
     });
+    console.log("[lafabrik:porte-strip]", {
+      candidates,
+      strippedCount: removed.length,
+      strippedNames: removed.map((c) => c.name),
+    });
     for (const child of removed) {
       child.removeFromParent();
     }

src/world/Lighting.tsx

@@ -98,6 +98,27 @@ export function Lighting(): React.JSX.Element {
       hasShadowMap: !!sun.current.shadow.map,
       ...counts,
     });
+
+    // [diag] temporary — track WebGL context loss/restore to correlate with shadow drops
+    const canvas = gl.domElement;
+    const handleContextLost = (event: Event) => {
+      event.preventDefault();
+      console.log("[ctx:lost]", { timestamp: performance.now().toFixed(0) });
+    };
+    const handleContextRestored = () => {
+      console.log("[ctx:restored]", {
+        timestamp: performance.now().toFixed(0),
+      });
+      if (sun.current) {
+        sun.current.shadow.needsUpdate = true;
+      }
+    };
+    canvas.addEventListener("webglcontextlost", handleContextLost);
+    canvas.addEventListener("webglcontextrestored", handleContextRestored);
+    return () => {
+      canvas.removeEventListener("webglcontextlost", handleContextLost);
+      canvas.removeEventListener("webglcontextrestored", handleContextRestored);
+    };
   }, [gl, scene]);
 
   useDebugFolder("Lighting", (folder) => {