Three harness corrections found while executing the invariant test:
- library type is 'ebooks' (plural) in library_types, not 'ebook'
- cleanup ordering: t.Cleanup is LIFO — register the pool Close BEFORE
the fixture's library deletes, or the deletes run against a closed
pool and fail silently into ignored errors (leaving RLSMARKER rows
behind; found because a second run saw the first run's 'deleted'
books still leaking through Recently Added)
- collection detail is addressed by the section's collection_id (the
UUID in view_all_url), not the section name