While it’s impressive work from the LLM and a TS implementation is novel, there’s at least a couple of pre-existing Python REs eg. https://github.com/jya-dev/supernote-tool :)
It seems like most of these "an LLM solved this in only X hours! " could have been "I found an open source solution that did what I needed with X minutes of web search."
Which doesn't mean that the LLM definitely couldn't have accomplished it without the prior art (in either the training set or explicitly in a a web search). But it does seem to be a trend.
I know of the project but it doesn’t actually extract the stroke information. It converts the raster into vector.
My reverse engineering extracts each pen stroke directly into a svg vector.