Dynamics for property "PreselectedOptionIndex"

### Description

Årsregnskap desires an opportunity to define preselectedOptionIndex based on a condition related to another datamodel.

Example: preselect valuta (RadioButton-component in subform) with "NOK" (e.g. [0]) in case orgForm != "NUF" (mainform).

### Additional Information

_No response_

Start by locating the existing PreselectedOptionIndex handling and the dynamics path for RadioButton components in subforms. Reproduce the example using a mainform condition such as orgForm != "NUF" and NOK as the desired selection; done means the option is preselected only when the condition holds.

Written by the indexing model from the issue text.