Good writeup. Thanks for sharing.
I started doing something on similar lines in which I give specifications in form of PlantUML to AI and let it write the code. It was driven out of the fact that AI was again and again writing duplicate code especially when context or session changed. I use Github copilot so far, but given its cost challenges starting this week will shift to something different.
I am going through your repo and now and I think the BDD approach is something I can learn from it to cover the gaps that I see in my PlantUML approach.