Chickens seem to possess amazing recuperative powers. Wash her wounds off with saline solution, then put Neosporin (NO Caine formula) on them. Check her often to see that the area doesn't get infected and especially keep her away from flies , even if she must be kept inside for awhile. Flies lay their eggs in wounds and once the maggots hatch they cause a whole lot of misery . and can migrate thru the body.
You could go to the predator threads and describe what happened to her, the wounds, and if you found any damage to coop/run etc. where predator came in. They may be able to pinpoint the type of predator and offer advice on eliminating them.
The predator will be back, so please beef up security in your coop and run. Look for any weak spots on construction or openings where preds can squeeze through.
If your birds free range, injury and loss is just something you have to accept. Chickens do not need to free range to be happy. If they have a nice secure, spacey run it's fine for them.