Integrate with macOS WidgetKit so we can show widgets in macOS Notification Center

I don't have any particular direct use cases in mind currently, but I was thinking the other day that it would be really cool if BetterTouchTool was able to integrate with Apple's WidgetKit (or other method if it exists) to be able to put content on the macOS Notification Center (aka: 'right hand widget bar' that can slide out from the right hand side of the screen)

A few resources I recently saved for exploring it for my own dev efforts:

I haven't explored what is actually possible to do with a Widget shown there (eg. how dynamic it can be); but for my (as yet unknown) use cases I was thinking that having the ability to write custom JavaScript code and/or render things with HTML/CSS there would be cool (similar to what is possible in other areas of BetterTouchTool currently)

It would also be useful to have access to Small, Medium, and Large widget formats (depending on what functionality can be supported) for better flexibility in their layout/usage.