// use serde::{Deserialize, Serialize};
// /// Request body for the login endpoint.
// #[derive(Deserialize, Serialize, Debug, Clone)]
// pub struct NewVarRequest {
// // pub message: String, // Arbitrary message signed by the client
// // pub client_pubkey: String, // Client's public key as a string
// // pub signature: String, // Base64 URL encoded signature of the message string
// }