Docker on windows looking interesting. I will follow that.
But, yes, for this project the HTML, JS and images are served by jetty, and when the POST, GET, PUT and DELETE methods are called by the designer, the responses are handled in Jetty which reads and writes the files on the disk.
I have the code working to read the file list, and file content. I just need to do POST, PUT and DELETE now.
I had a response on the github issue which pointed me in the right direction. It was really just my misunderstanding of what the payload looks like. I'll commit when I'm done. Hopefully this weekend or next.