[IDEA] - Checkbox

[Inedable]

Since Discord released forums, I actually use it for productivity TODO lists.

They added some new markdown features like heading and bulleted lists.
It could be nice to add additional checkboxes like the ones we can see on GitHub :

• Checkbox ⇽ - [ ] Checkbox
• Checkbox ⇽ - [x] Checkbox

As it is possible on GitHub, it could be nice to add the possibility to toggle it, on a click event, it would automatically update the message (and the markdown message).