Implements empty responses for the fake project read model. Instead of
throwing a not implemented error, we'll return empty results.
This makes some of the tests in enterprise pass.
Hooks up the new project read model and updates the existing project
service to use it instead when the flag is on.
In doing:
- creates a composition root for the read model
- includes it in IUnleashStores
- updates some existing methods to accept either the old or the new
model
- updates the OpenAPI schema to deprecate the old properties
