Fixtures were produced by CultLib 0db1fe5 from a temporary worktree: a v4
directory store and a v1 single-file store holding the same three records.
Tests reopen both and assert every value, and assert the directory store
refuses v1, v1.directory, v2 and v3 manifests without touching the bytes.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>