Currently I can make an app from a function which is triggered from a web request. I want a private function that cannot be accessed/triggered without authentication. Basically port all functionality of serverless functions into apps that have function resources.

The reason to use an app function is that apps can be given access to managed databases, so I either want that feature (https://ideas.digitalocean.com/app-framework-services/p/serverless-as-trusted-db-source) or this one.