I can't tell about the extra toes or whatever, but she appears to have scaly leg mites. You will need to treat your coop for mites, but for the feet, apply castor oil or vaseline weekly to the feet and legs and thoroughly rub it into the scales. Soaking the legs in warm soapy water, and gently brushing the legs with a toothbrush to loosen the scales just before treating them would also be good.