The basic problem was that I had created an App Intent extension and put the files into the extension. Apple's documentation on the developer site does not make it clear that this is the correct way to configure the project... I had assumed I needed an App Intent Extension because I saw it existed in the "New Target" menu. I moved the files back to the base app and deleted the app extension and the error about not finding the intent stopped appearing in the console.

The second issue I had was that my model type was creating a UUID identifier as part of its init. To work properly with VI, your model types need to have a STABLE identifier as the identifier will be used across processes.

Once I corrected those two issues, my PoC app worked as expected.