If you want it to be a still cider, you can just add a couple of campden tabs, give it 12-ish hours, and then add sugar to sweeten to taste.
If you want it to carb later, I think you can use lactose to ferment it. I've never done it, but lactose is unfermentable, so adding it should sweeten it without raising your ABV (or causing bottle bombs... hooray!).