Authenticated directory deletion via cluster hello traversal

Path traversal in cluster hello handling in Wazuh manager before 4.14.6 allows remote authenticated users to delete directory contents. AbstractServerHandler.hello accepts a peer-supplied node name without validation, and clean_up later joins that stored name into the cluster working path with path.join instead of a containment check before remove_directory_contents runs on disconnect. Exploitation requires cluster-network reachability and a valid Fernet key for peer authentication; deletion is limited to directories writable by the wazuh user under the Wazuh installation path, but wiping etc/ can keep the manager from starting after the next restart.