Run 13 failed at the same helper: the store holds LockFileEx locks on wanderbooks.lock and books.lock, which are mandatory on Windows, so reading them is refused. tree() skips any *.lock and the live SQLite files at any depth. The other read_dir walkers in the store, cli and gui tests either read only metadata or copy closed books; the cli harness's book_files already tolerates a refused read. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01HS8WZziDnyxunC23MUxrLp