It sounds like you're not really over the job. If you were, you would be fixedly focused on getting a new one. So my guess is that anything you do about pulling back effort or leaving whilst working from this mindset is going to be half-hearted. I personally think advice on this matter will be wasted, because if it mattered to you, you would have figured out an answer to your question yourself. People naturally drag their feet on things they don't believe in and aren't excited for, it's not a learned skill.

Anyway, if I'm right, it follows that you're struggling to do the bare minimum because people who care don't do the bare minimum, they do their best, often at expense to themselves.

I would suggest maybe you try to come up with some rules (no emails before X AM or after Y PM, answer emails at least 1 day after receipt, work no overtime unless asked) and you could practice them until it becomes reflex. On top of this, I find it useful to look at what your 'worst' peers are doing and slowly adjust the pace of work to meet them if you're outperforming them.

Whatever you do, start the search for a new job now. It takes time and applying and interviewing is a skill that you should practice, something amazing may come up and you can go for it, but you won't know unless you look. If you're aiming at big companies, you don't want to have to wait to the last minute when they give you notice to start grinding leetcode questions, do you?