The Windows CI job failed on:
assert '/.mempalace/state/' in str(state_path)
because Windows uses ``\`` as the path separator, so the substring
never matches. The behavior under test (state file lives outside the
diary dir, under ``~/.mempalace/state/``) is already correct on both
platforms — only the assertion was Unix-only.
Switch to ``state_path.parent`` comparisons that work on any OS.
Igor Lins e Silva
7192552624