fix: prevent path traversal vulnerabilities in ZipConverter
Added a secure check for path traversal vulnerabilities in the ZipConverter class.
Now validates extracted file paths using `os.path.commonprefix` to ensure all files
remain within the intended extraction directory. Raises a `ValueError` if a
path traversal attempt is detected.
- Normalized file paths using `os.path.normpath`.
- Added specific exception handling for `zipfile.BadZipFile` and traversal errors.
- Ensured cleanup of extracted files after processing when `cleanup_extracted` is enabled.
