export declare function encryptNip44(plaintext: string, conversationKey: Uint8Array, nonce?: Uint8Array): string; export declare function decryptNip44(payload: string, conversationKey: Uint8Array): string; export declare class Nip44 { private cache; createKey(privkey: string, pubkey: string): Uint8Array; private getKey; encrypt(privkey: string, pubkey: string, text: string): string; decrypt(privkey: string, pubkey: string, data: string): string; }