- last_modified_time takes DateTime directly, drop the Some() wrapper
- file_names() returns Result<Cow<str>, ZipError>: propagate errors, compare
the Cow<str>, and push the resolved name into seen
- test helper: ZipFile::name() now returns Result, unwrap it
- update the Cargo.toml comment explaining why we moved ahead of
SolidCraft (still on zip 3)
- update Cargo.lock to zip 9.0.3