Well, you can either wait for him to want to stop or you can take action and be prepared for a bit of upset. Not having everything you want all the time is part of life, it won't harm him! Within a couple of days your supply will reduce anyway.
With DD I reduced feeds to only being after each meal, then I cut them out one at a time. Would offer warm milk in a cup while I cuddled her instead.
Early morning wakes - you're going to have to decide if feeding him to sleep for an easy life is worth more to you than not feeding any more. I'd take him back to his bed and offer water and a cuddle, or let him in with you but no milk. Make yourself wake up to stop him feeding, just say 'we'll have some later'.
I can entirely understand the bodily autonomy thing, I don't think weight loss will be any easier to achieve if you're not breastfeeding but I do get the thing of wanting to reclaim your body.
Really I think you need to toughen up a bit. Gentle parenting is supposed to be a balance that suits both parties. It's too easy for it to end up being a martyr mission where you think if you don't give your child everything they ask for/want, they'll be harmed. And that any upset is to be avoided at all costs. I don't think that approach is a good preparation for life.
You can be compassionate, caring, sensitive, have a close bond - and still put your foot down on some issues. I also think it's healthier to say no than to accept what children want but feel resentment and frustration about it. I don't mean that to sound like I'm having a go at you, it was my own realisation from giving too much in constant feeding and co-sleeping.