* [Toucan 2 prep] Don't invoke Toucan models as functions

* Some fixes

* Test fixes

* Test fix

* [Toucan 2 prep] Don't call `type` or `class` on Toucan models

* Test fixes

* More test fixes 

* Replace perms protocol with multimethods; derive models from perms policy keywords

* Test fixes 

* Appease Eastwood

* Fix errors now that App has been merged in

* Empty commit to trigger CI