fix: export setCamera from SpatialMemory (#1167)

Entity resolution lines were drawn but LOD culling never activated because setCamera() was defined but not exported. Without camera reference, _updateEntityLines() was a no-op.

nexus/components/spatial-memory.js

@@ -829,7 +829,7 @@ const SpatialMemory = (() => {
     getCrystalMeshes, getMemoryFromMesh, highlightMemory, clearHighlight, getSelectedId,
     exportIndex, importIndex, searchNearby, REGIONS,
     saveToStorage, loadFromStorage, clearStorage,
-    runGravityLayout
+    runGravityLayout, setCamera
   };
 })();