Take a look at this topic, which explores a similar question.
There are special bits for milling foam, but they are pricy. Also, if I remember correctly, best results are had with conventional milling instead of climb milling.
I recently bumped into an interesting phone app that I wondered if it could be used for this purpose. It is called Adobe Capture. It is free but it does require a (free) Adobe account to do anything significant with it. It can directly take vector (SVG) images, and it has some object recognition built in.