Auth: Add project query parameter to URLs in authorizer.

[markylaing]

In our implementation of (github.com/openfga/openfga/pkg/storage).OpenFGADatastore, entity URLs are expected to include the project query parameter even if it is the default project. However, LXD typically displays URLs without the project query parameter when a resource is in the default project (with the exception of permissions, where we have been explicit).

This PR ensures that the project query parameter is added to URLs inside the Authorizer so that this doesn't need to be done elsewhere in the codebase (such as in project.FilterUsedBy which has now been simplified).

Closes #13072 Blocked by #13262

[markylaing]

@tomponline This is ready for review when you have time. Thanks.