/**
 * Extract the time portion from a UTC datetime string.
 *
 * - Uses Temporal.Instant.from to parse, converts to specified timezone.
 * - Defaults to UTC if no timezone specified.
 * - Returns "" for invalid input.
 *
 * @param value ISO UTC datetime string (e.g., "2024-03-17T14:30:45Z")
 * @param options optional: timeZone (IANA)
 * @returns ISO time string (e.g., "14:30:45") or "" on invalid input
 *
 * @example parseTimeFromUtc("2024-03-17T14:30:45Z") // "14:30:45"
 * @example parseTimeFromUtc("2024-03-17T14:30:45Z", { timeZone: "America/New_York" }) // "10:30:45"
 * @example parseTimeFromUtc("invalid") // ""
 */
export declare function parseTimeFromUtc(value: string, options?: {
    timeZone?: string;
}): string;