Move TypeScript toggle button to MDX

[gragland]

We want the TypeScript toggle button to appear between the post description and the code example. Looks like moving it into MDX is the best way to do that.

[gragland]

@bozheville do you still have time to handle this one?

[bozheville]

@gragland I am. Sorry for the long delay, I am trying to find not too hacky implementation

[gragland]

@bozheville Cool, no worries, just wanted to make sure :)

[bozheville]

@gragland small update. It's in progress. Hope to complete it within the next week

[gragland]

@bozheville Awesome, thanks for the update!