/**
 * Validates a value that will be interpolated into a URL path segment and returns it
 * unchanged when it is safe. Throws when the value is empty/whitespace or contains a
 * path separator or traversal/query sequence that could hijack the request route.
 *
 * @param value Raw value to be placed into the URL path
 * @param segmentName Human-readable name of the segment (used in the error message)
 */
export declare function assertValidUrlPathSegment(value: string, segmentName: string): string;