All services errors to match application errors

[pete-rai]

Ambassador will return consistent error codes to the BBK core services. However, Ambassador returns body-less errors, which is not the same as BBK core - which always returns an error body. Even for 404 and 401s and such:

https://www.bit-broker.io/docs/api-conventions/errors/

Errors coming from any "fronting" component, should be changed to match this format. This includes the rate-limiter and auth-service. This is because the user should not be aware that the error is coming from a "fronting" service.