/**
 * Decode a single top-level CBOR item from `bytes`. Trailing bytes
 * throw — WebAuthn structures are self-contained and any leftover
 * suggests a truncation or injection attempt.
 *
 * @param {Uint8Array} bytes
 * @returns {unknown}
 */
export function decode(bytes: Uint8Array): unknown;
/**
 * Decode one item and report how many bytes it consumed. Used by
 * parsers that read a CBOR blob followed by other data — the
 * authenticator extensions map at the tail of authData is one such
 * spot.
 *
 * @param {Uint8Array} bytes
 * @returns {{ value: unknown, bytesRead: number }}
 */
export function decodeWithLength(bytes: Uint8Array): {
    value: unknown;
    bytesRead: number;
};