/**
 * Return true if `value1` and `value2` form a valid zoned range — both parseable as
 * ISO ZonedDateTime strings and the instant at `value1` is <= the instant at `value2`.
 *
 * - Both inputs must be valid ISO 8601 zoned datetime strings.
 * - Equal `value1 === value2` is valid when `options.allowEqual` is true.
 * - Comparison is done by instant, so intervals spanning DST transitions are compared
 *   by absolute time.
 * - Invalid input, malformed strings, or leap-second strings return `false`.
 *
 * @param value1 first ISO ZonedDateTime string
 * @param value2 second ISO ZonedDateTime string
 * @param options optional allowEqual flag
 * @returns boolean indicating whether the zoned range is valid
 *
 * @example isValidZonedRange({ value1: "2024-01-01T10:00:00+00:00[UTC]", value2: "2024-12-31T23:59:59+00:00[UTC]" }) // true
 * @example isValidZonedRange({ value1: "2024-12-31T23:59:59+00:00[UTC]", value2: "2024-01-01T10:00:00+00:00[UTC]" }) // false
 * @example isValidZonedRange({ value1: "2024-06-15T12:00:00-04:00[America/New_York]", value2: "2024-06-15T12:00:00-04:00[America/New_York]", options: { allowEqual: true } }) // true
 */
export declare function isValidZonedRange({ value1, value2, options, }: {
    value1: string;
    value2: string;
    options?: {
        allowEqual?: boolean;
    };
}): boolean;