Hemingway App-like integration #647

Hej,

first of all I love the app!
I was wondering if there could be an implementation of a proofreader, like the Hemingway App.
Hemingway is not open source from what I could see, but there are some similar libraries that do the job. I could find this article: https://dev.to/samwsoftware/creating-my-own-hemingway-app-143
and this apparently dead github-repo: https://github.com/kdzwinel/Proofreader (or it's perfect?)
Anyway, I think this would be a great feature that would distinguish the text app even more from other apps out there. I don't know any service apart from hemingwayapp.com that has such a proof reader.
Thanks for your efforts with the app, really beautiful!