/**
 * Strip everything but digits, then drop leading zeros — Poalim pads its references
 * and security keys with zeros inconsistently between the reference column and the
 * transaction description, so comparisons must happen on the normalized form.
 *
 * Returns null when the result is too short to be a meaningful reference (guards
 * against matching amounts, dates and other incidental digit runs).
 */
export declare function normalizeNumericReference(value: string): string | null;