Make batteries be able to removed by click dragging battery container into offhand

[Ikea]

Name explains most of it, rn the only way to remove a battery from an item is to swap it with another battery, this behavior isnt really intuitive, and sucks for qol. Anytime you want to get an artbattery from an artgun, you go on a fetch quest to find one battery that isnt in an item, so either make your own or steal from sec for the practical ways to do it.