Split play2 code-store into separate stores

[codicocodes]

The complexity of the code-store is growing, once the integration with the nestjs-backend is more stable we want split this store up into smaller reusable stores.

The stores will still have some dependencies on each other, so we will need a service in order to facilitate that exchange. TBD how it will look and work.

I think I will grow the monolith store until the behavior is stable, and then figure out how to best extract separate functionalities.

[codicocodes]

API is relatively stable, have not touched code-store in months. Can be improved with refactoring out several of the methods to be outside of the store.

If you want to take this on, please take a look at the current store and how you'd want to split it and improve the API, and we can have a discussion.