Model access control

Access to models is dependent on the user permissions.

• Only administrators are able to see all models, including those not created by them.
• A user, who is an owner of a given model, can set the visibility of the model to public or private on the AI Regsitries UI.
• When a user registers a new model, the user becomes the owner, and no other user has access.
• A user can make the visibility of a model public, and then all users receive viewer access to the model by default.