Allow linking lists to `type: string` props

Overview

Unless we allow linking lists to type: string, using lists requires building components that include content model expectations.

Example scenario for this could be that we allow selecting 3 levels of difficulty; Beginner, Intermediate, Advanced. To display this, you simply want to display the value selected on the list for the end-users.

Proposed resolution

Allow linking lists to `type: string` props. In this scenario, the mapping would specifically target the human readable lable of the selected option.

User interface changes