Loco Translate <= 2.8.2 - Authenticated (Translator+) Path Traversal to Limited File Read via 'ref' Parameter

The Loco Translate plugin for WordPress is vulnerable to Path Traversal in all versions up to, and including, 2.8.2 via the `fsReference` AJAX route. This is due to the `findSourceFile()` method normalizing user-supplied `ref` paths containing `../` directory traversal sequences without validating that the resolved path remains within the intended bundle or content directory. This makes it possible for authenticated attackers, with Translator-level access and above (custom `loco_admin` capability required, granted to the `translator` role and administrators by default), to read arbitrary `.php`, `.js`, `.json`, and `.twig` files from the server filesystem outside the intended translation directory. Files named wp-config.php are excluded.