Don't load the whole digging area when only a small piece is relevant.
Also, move the (time expensive) check whether the air above a block is free to the last position, which spares unneccessary checks when multiple quarries are placed together, or a quarry has to loop over air for another reason.
Supply the on_refill hook for power tools and cans, to perform appropriate
charging. This is to be used by unified_inventory's creative-mode
refill slot.