Her new sleep pattern has disrupted the way your household worked and you weren't prepared for that. So I think it's understandable that you feel unsettled about it. It does seem like you (and especially your DH) are having trouble cutting the apron strings and accepting that she can dictate her own life more now.
I think I would be concerned if it was going to continue like this through university term time (though even then, I'm not sure you dictate otherwise unless it causes disruption or ends up with her being out of uni and failing to find her way in life). If it's a temporary thing for a couple of months until uni starts then I think you would be a bit controlling to stop her. It's an opportunity for her to indulge a passion she has and she isn't going to get that much more time to do it so fully.
You might be reasonable to insist she spends some time one day a week with the family as a whole but your DH IBVU to say the rest of you can't go out if she doesn't come too. That's just punishing everyone else. Is he trying to guilt her into coming or is some sort of sulk?
I don't think you are unreasonable to say she should pay for the food she wants to use when she cooks for herself if it's an extra expense for the household, learning to deal with the consequences of her choices is an important step to self-sufficiency. However, she probably won't be eating with you much when she's at uni either and you weren't planning on charging her board, perhaps you should reconsider that?
Mainly I think you need to accept that just because she's living at home while she goes to uni doesn't mean it's going to be like when she was in school. She's grown up and is going to be making her own way in the world. That's going to include some mistakes and poor decisions and you're going to have to let her make those. It's going to include a bit of selfishness and prioritising her own needs and desires over yours. In some ways she's going to be more like a lodger than the daughter you are used to, and that's OK. It's good, even, if you want her to use her uni time to gain some independence. You should perhaps have a talk with her about how you miss her and would like her to plan a bit of time with the family from time to time.