It's very good that you gave her some electrolytes if you really really care you could take her to the vet but other then waiting it out I don't know if chickens can get rabies or not make her some hard boiled or scrambled egg and give her lots of rest I'm so sorry that happened to her
Sadly, the chances of finding a vet that wouldn't laugh you out of the building in a chicken related situation are quite small. If you DO find a chicken vet, feel extremely lucky and thankful!
Anyway, this bite should be coated with triple antibiotic after cleaning and drying, and she should be watched carefully for severe problems. You may have to make an unpleasant decision, though, because the rat's tooth might have reached the brain. If that has happened, it's doubtful she will recover without problems.
