In my experience working for other people it normally only gets worse, not better. I don’t mean to say that you shouldn’t put in effort or try hard at work—what I mean is that broken or toxic environments tend to only get worse. People with the ability and the self-respect tend to leave if they see an interpersonal or a structural dumpster fire. I would find another job and I wouldn’t worry about your résumé having a short blip on it. You’d be surprised how many people have a similar story about starting at a company and immediately realizing it was a mistake.