You can keep her in tonight as she is probably exhausted and youll also be able to monitor her and make sure she is eating and drinking, that's the best option. If she seems ok and like the other chickens aren't bothering her and she can roost that's probably fine. But you won't be able to monitor if she's acting ok or if the others are bothering her.
It's good that she ate something and that she has no wounds. As long as she's acting normal and whatnot she'll be just fine.
Keep us updated I hope Cashew feels better in a little bit, she's really cute.