I'd stop all the discussion about the morning - too much thought going into things (like whether or not there are muffins) and she's focusing on all that activity instead of on calming down. If you really need to tell her a day ahead that you'll pick her up from school, tell her that at 4 PM. The next morning is the time to remind her of what was decided yesterday. Daddy can get her up and give her muffins and whatever the deal is. I think you are giving her too much stimulation at night by going through the whole routine. If you want to lay out her outfit the night before to minimize distractions in the morning, fine, but do it at the very start of the bedtime routine. The bedtime routine needs to be consistent, as you say, but I'd focus more on what actually calms her down than on what she WANTS to do. I'd move bedtime up to 8 PM instead of 9 PM, and I'd say she can get up for the potty and NOTHING ELSE.
We used to sing "Good Night Ladies" but change the words to "Good Night, David (3 times), it's time to go to sleep." Then we'd add in some verses about the past day, not the next - "We had a good day, we went to the zoo,…." just making up words and squeezing them into the melody by just mashing up some syllables. Nothing exciting, just calming. Then we added in "Sweet dreams, David….", getting quieter and quieter, and slower and slower. We found his breathing calmed down, his squirming calmed down, and the constant singing by one of us kept him from interrupting and making conversation. It was the same idea as a story (when kids are quiet and listening) but done with the lights off (or with a nightlight on). We usually lay down near him but not so close that he'd sense us getting up as he dropped off to sleep, but you could also do it sitting by the bedside and rubbing her head or holding her hand.
If she's totally capable in the bathroom, leave the light on in there and not in any other rooms, and tell her she can go there on her own, with no talking. The other thing you can do is put a kiddy potty in her room and leave the nightlight on. Put some squares of TP next to it or put some wipes there, whatever she's used to. She's probably just peeing, not pooping, right? So since urine is technically sterile, she doesn't need to wash extensively. I don't like hand sanitizer and I think it adds an extra step, but if you feel strongly about it, you could put some there. But I imagine she would just play with it. Anyway, she doesn't get to come out of the room to use the bathroom because she's coming to you and talking, getting drinks, getting hugs, giving you her baby, etc. etc.
You could put her in a pull-up so she isn't nervous about staying dry all night, if you want to make the break from diapers. Most kids are not reliably dry at night at the age of 3 - and they are often agitated about being a "big girl" when they are asleep.
I think you have to take her choices out of the bedtime routine - the discussion of why you decided certain things (like muffins) is getting her riled up so she can't calm down, so she has a tantrum.
You could also try a CD player of lullabies that taper off in volume, or an air filter type device that provides white noise if you think she is reacting to house noises. For some kids, it blocks out other stimuli and helps with constancy.
If you have to, take a few nights on a weekend when she doesn't have to get up for school, and keep putting her back to bed without talking or engaging her, and put a childproof doorknob lock on the door so she cannot get out. It's her choice to go to bed or to scream. Put the potty in there so there's no nonsense with having to pee. But no, she stays in her room for the night until she can stop getting up to wander around. Eventually she will get tired and if the potty is there she won't be wet. SHe's doing this because she can - she's getting a payoff for it. And that payoff is your attention.
But don't keep changing it up every single night. That will make things worse.