Can I pass props to config.js?

I’m writing a configurable Forge app with CustomUI. As part of the configuration, I’d like the user to be able to enter the name(s) of a user or group.

Ideally I’d like this to work the way Confluence works when you’re, for instance, assigning permissions - you start typing in the box, and a drop-down appears with suggestions.

In order to do this, I think I need config.js to have access to a list of all users and groups. Is there a way to get this information into config.js by passing it in? Or can I retrieve it from within config.js (e.g. by calling a resolver function or invoking the api directly)?

Or is there a better way to do it?