I think the answer is “no” at this point, but I was hoping for confirmation on the matter.
TLDR;
I honestly didn’t know much about either, but I had seen custom Icons. I just happened to use ‘WIP’ as my starting point, which has both an Action, and an App.
Items in Image: (GitHub Workflow, GitHub App, GitHub Action)
When I initially was researching (Googling) this question, I ended up at ‘github.com/actions/starter-workflows/’ and I miss interpreted the whole \<name\>.properties.json
and ‘icons/’, as something I could utilize with ‘Workflows’. I understand now that this is actually “content” repo.
I guess I was expecting a question to be on StackOverflow or some other site by now. Maybe I was just using the wrong keywords.