UX error prevetion feature: Short delay before boosts and likes are submitted

[DanConwayDev]

I just boosted my first note by mistake!

What if I accidentally boosted or liked something that I really didn't want to show my support for?

Two competing proposals:

1. when the button is pressed its state changes to loading for 1-2 second in which time the action can be cancelled by pressing the button again.
2. the action appears to be sent immediately but is actually delayed by 5 seconds in which time the user can cancel by pressing the button again.