CiviConnect: Detect changes in app metadata and prompt for approval

Suppose an admin connects to the application "Foo Address Cleaner". The application's `metadata.json` includes a request to access the entities "Contact", "Address", and "Email", and the admin approves.

A month later, "Foo Address Cleaner" adds support for cleaning phone numbers, so the vendor updates the `metadata.json` to request access to the "Phone" entity.

Currently, the admin must take initiative to re-register (ie call "Cxn.register" again with the existing cxnId but new permissions).

Civi should display an alert and prompt for administrative review. Upon approval, it should re-register.