Flag data model field to be displayed in relationship dropdown

**Is your feature request related to a problem? Please describe.**
Using Amplify Studio to create a data model with 2 two models (e.g. Location & Exhibit) having a one to one relationship to each other. When an editor maintains/edits content in the Locations-model it is necessary to assign an Exhibit to this Location. In the Amplify Studio content-tab the editor gets the corresponding dropdown to select an exhibit in the Location model "Exhibit" field. So far so good. This list displays the IDs of the exhibits and an apparently randomly selected additional field to identify an exhibit record. Unfortunately this randomly chosen field is an ENUM containing a brand name. It is not possible to identify the correct "Exhibit" for this Location by ID (IDs of Records are not displayed in Amplify Studio Content) nor by the brand. This problem is only related to Amplify Studio and not the schema.

**Describe the solution you'd like**
It would be great to have the possibility to flag one (or more) field(s) in the Amplify Studio data model as e.g. "display in relation field dropdown". This flag causes this filed's content to be displayed in the dropdown when selecting a relationship record in the other type. Please see the screenshot below to get the problem.

**Describe alternatives you've considered**

**Additional context**

The issue identifies the Amplify Studio content tab and its relationship-record dropdown, but no files, tests, or entry points. Start by tracing how relationship options and data-model fields are represented there; done means allowing one or more selected fields to control the identifying text shown for relationship records.

Written by the indexing model from the issue text.