❯ grpcurl -plaintext -d '{
  "username": "testuser2",
  "email": "test2@example.com"
}' localhost:50051 multieko2.auth.AuthService/Register
{
  "id": "5fa9bbce-85e0-4b06-8364-b561770c2fdd",
  "username": "testuser2",
  "email": "test2@example.com",
  "role": "accountant"
}