Workflow won't run if an input port is empty, but rodan won't tell you why

If an input port in a workflow is empty, rodan still indicates the status of that workflow as 'valid'. However, if you try to run the workflow, nothing happens; but since rodan thinks the workflow is valid, there's no indication of why the workflow isn't running.

I came across this issue when I was trying to run an IC workflow. The IC job already had a 'Training data' input port, but I was running the IC for the first time, so I had no training data to give it. I figured I would just leave the port empty, since the IC doesn't need training data to work. But when I tried to run the workflow, nothing happened, because a port was empty. Once I had removed the empty port, the workflow ran just fine:

https://github.com/user-attachments/assets/d70b5ee7-de70-4c05-9449-1135aeef1f7e

I think it's totally fine that a workflow won't run if a port is empty. My requested fix would be that if a user tries to run a workflow with an empty input port, Rodan warns the user that won't be possible, and tells the user why.