I haven’t tried the linked extension above, but my main concern with it is: will the dev stay on top of maintenance? There’s nothing more frustrating that having core feature of your IDE stop working 
I’d rather see an official plugin from Unity or Cursor.
However a viable workaround I’ve been using for now is having Unity still pointed at VSCode as its external script editor. That way it will generate the .csproj files Cursor needs for intellisense. The only downside is that opening a script within Unity will open VSCode instead.