Auth is the service tasked with creating and validating jwt tokens.

UserClaims is a custom struct used as jwt payload.

UserSvc is our service struct that implements the services.UserService interface.

Rationale: Ideally these methods say what they do according to business value in this example however it's really just CRUD-only.

Rationale: It's tempting to name your methods like they are below, but this is actually a bit of a smell it will make you wonder why you need this interface if it looks a lot like storage.WebhookStorage.