export interface BlobEncryptionParams {
    iv: string;
    tag: string;
}
export interface EncryptedBlob extends BlobEncryptionParams {
    ciphertext: Uint8Array;
}
/** Encrypts blob bytes with AES-256-GCM under the app's secret key. */
export declare function encryptBlobBytes(data: Uint8Array): EncryptedBlob;
export declare function decryptBlobBytes(params: BlobEncryptionParams, ciphertext: Uint8Array): Uint8Array;