Uploading image files to WordPress via WPCOM interface

[scripting]

I've been working on this Node.js package to provide easy browser-based JavaScript interfaces to the common WPCOM functions for working with WordPress websites.

Most of it has been going pretty smoothly, but I've been having trouble with uploading image files.

I created this gist, to show one of my attempts, I've tried lots of approaches, based on docs I've been able to find, and working with ChatGPT and Meta.ai, both of which took some pretty wild guesses which indicates to me that it doesn't have a lot of good sources for this.

https://gist.github.com/scripting/1fc3f656748dbaa3d84aefc1322aa72c

Any help much appreciated!