/**
 * Cluster Secret
 *
 * Shared secret for inter-server auth in client mode.
 * Stored at ~/.nebula/cluster.json with 0600 perms.
 */
export declare function readClusterSecret(): string | null;
export declare function writeClusterSecret(secret: string): void;
export declare function getOrCreateClusterSecret({ allowCreate }: {
    allowCreate: boolean;
}): string | null;