/**
 * Extracts the PDF filename from a URL.
 *
 * Parses the last path segment of the URL looking for a `.pdf` extension.
 * Falls back to `"document.pdf"` if no valid PDF filename is found.
 *
 * @param documentUrl - The URL of the PDF document.
 * @returns The extracted filename (including `.pdf` extension), or `"document.pdf"` as a fallback.
 *
 * @example
 * ```ts
 * getFilename('https://example.com/files/report.pdf'); // "report.pdf"
 * getFilename('https://example.com/download?id=123');   // "document.pdf"
 * ```
 */
declare const _default: (documentUrl: string) => string;
export default _default;