Granular inbox management permissions

Separate inbox management permissions so that a non-admin has permissions to manage shared inbox access without also having the permissions delete, create, or edit the inbox properties. We must be able to do this outside of teammate group management because we often need to grant users direct access to an inbox without being impacted by any rules a teammate group is associated with.

We cannot grant business users the ability to manage inbox access if they have the ability to delete, create, or edit inbox properties. Based on previous errors observed, too many users make errors or exercise inappropriate authority, and we cannot risk inbox creation/deletion/editing.