Implement ability to render actual elements

[kepstein23]

As a user I want to see what elements will look like on a participant's interface.

This can probably be copied from deliberation-empirica. We know it will be used in the render panel but may want to be used in the Timeline as well for users to preview each element individually.

The challenge here will be to fetch the appropriate files for the prompt especially.

[kepstein23]

After talking with James, we'll import deliberation-empirica as a sub-module and use those files directly.

[JamesPHoughton]

There is a good start on this in kimberly's branch, we'll need to merge it and get the tests running

[JamesPHoughton]

todos:

• add additional components
• mock stage timer
• use windii CSS from deliberation-empirica in render window
• force everything to render inside render panel