**suggestion:** Type the signup function parameter

[Shloimy15e]

          **suggestion:** Type the signup function parameter

Similar to the login function, consider creating a specific type for the signup data instead of using 'any'. This will improve type safety and code clarity.

interface SignupData {
  username: string;
  password: string;
  email?: string;
}

async function signup(data: SignupData) {

Originally posted by @sourcery-ai[bot] in #35 (comment)