/**
 * Registers an ML-DSA-65 public key with the registration worker.
 *
 * @param registerBaseUrl - Worker base URL (no trailing slash)
 * @param publicKey - Raw ML-DSA-65 public key bytes
 * @returns Server-assigned `key_id`
 * @throws Error if the HTTP request fails or the response is invalid
 */
export declare function registerPublicKey(registerBaseUrl: string, publicKey: Uint8Array): Promise<string>;