Macworld Apple’s Focus feature is designed to let you shape your interruptions. Do you want to get no calls, FaceTimes, or messages? No alerts from apps? Or would you like to let certain important or particular people and things through to make sure something that should break your concentration appears? In particular, you might want to always let a set of people reach you by a voice call on your iPhone. Depending on your age, it may be rare or unheard of to get a phone call—or you may place and receive them all the time. But for most people, a phone call from a select group of people can be s…