Better StatusResponses #2
Description
We currently return on almost all of our GRPC responses a StatusResponse, where "success" or "error" is being returned in a string.
I think we need to change this and return an enum instead of a string, because it would be better to know what exactly went wrong, so for example we could return GROUP_ALREADY_EXISTS, if a group already exists instead of just error.
This would make working with the api and the error handling a lot better