OnePlus’ debut mechanical keyboard is a Keychron with a twist You get extra keycaps and a combination switch/keycap puller in the box.OnePlus’ debut mechanical keyboard, the Keyboard 81 Pro, may be little more than a redesigned Keychron Q1 Pro with a couple of tweaks. But the Keychron Q1 Pro is one of the best mechanical keyboards available today, and the tweaks OnePlus has made to its design range from “i…