The Arcturus errors "page hierarchy contains a cycle page 354 and 357" and "sibling order 1 is used more than once (111 problems)" come from catalog_pages, not catalog_items: pages 354/357 point at themselves, and many parents have child pages sharing the same order_num. Extend the emulator catalog scan + fix to detect both: pages whose parent chain loops back get detached (parent_id = 0 on the highest cycle member) and every affected parent's children are renumbered sequentially, preserving their current relative order. Add scripts/diag-emulator.ts to inspect the live catalog state.