Function parse_legacy_encrypted_backup 

pub(crate) fn parse_legacy_encrypted_backup(
    local: &[u8],
    consensus: &[u8],
    private: &[u8],
    salt: &[u8],
    password: &str,
) -> Result<ServerConfig>

Parses the legacy encrypted guardian backup format from raw file contents, decrypting the private config with the provided password. The salt and private bytes come from the backup’s private.salt and private.encrypt entries.