Format all marketmaker API responses

The API responses we get from `marketmaker` or often not that well formatted.

Currently, sometimes we are using them as is and pluck out the properties we need, sometimes we format them into a more usable structure.

We should really refactor the API client to format every response in a clean structure and use that structure everywhere.

This will also have the benefit of meaning we can use the API client as an API reference/documentation. The official docs are lacking and sometimes incorrect.