/**
 * Return the second (0-59) from a UTC datetime string.
 *
 * - Returns zero-padded string for second.
 * - Returns "" for invalid input.
 *
 * @param value ISO UTC datetime string (e.g., "2024-03-17T14:30:45Z")
 * @returns Second (00-59) or "" on invalid input
 *
 * @example parseSecondFromUtc("2024-03-17T14:30:45Z") // "45"
 * @example parseSecondFromUtc("invalid") // ""
 */
export declare function parseSecondFromUtc(value: string): string;