In the new logged in designs, users can favourite collections they want quicker access to when logged in. The intention is to enable them to separate the items they're really interested in from everything that's available to them through the Library Bundle.
The design work is ongoing for the front-end component of this, but we can implement the back-end functionality in the meantime.
We might initially assume that this system should be a relationship between users and authorizations, but Bundle collections all have the same authorization, so this needs to be a relationship between user and resource objects. This does ignore collections, but for the few users with access to multiple collections from the same resource this is an oddity we'll opt to live for simplicity with until collections are deprecated.
**Acceptance criteria**
- There is a new relationship for defining which resource objects a user has favourited
- The relationship should be ManyToMany, but we need to avoid a circular dependency between user and resource models