This is funny because I was in the same situation, and actually used Claude to make a custom CAD program inspired by OpenSCAD :) https://fncad.github.io
You definitely need to have a strong sense of code design though. The AIs are not up to writing clean code at project scale on their own, yet.
This is a good example of what I mean! fnCAD appears to be a significantly buggier and highly incomplete version of OpenSCAD, where AI essentially grabbed the low-hanging fruit - albeit an impressively large amount of fruit - and left you with the hard parts. I fail to see how this solved any problems. Maybe it was an experiment, which is fine. But it's not even close to a viable CAD product, even by OpenSCAD's scruffy FOSS standards, and there's no feasible way to get it there without a ton of human work.
Not trying to denigrate the work here, as such. But this certainly didn't convince me that using AI to replace OpenSCAD (or any other major open-source project) is a good idea. The LLMs still aren't even close to being able to pull it off.