I also think that role-playing is a good idea. There unfortunately will be a million Roses in her life's pathway.
But I think that another good tool is for a child to learn to evaluate the situation, and think about who's making the rules, and who actually has a right to make the rules.
Examples: They're all playing at Rose's house. Rose's mother says no cookies right now, and Rose says "let's all sneak down and get cookies". Your daughter stops and thinks: who's in charge here? Of course, the mommy. So, no cookie-stealing.
Playground: Teacher or aide is supervising, Rose suggests pushing someone down the slide even though that's just what the teacher said NOT to do (use whatever example is appropriate for your child's school playground). Who's in charge? The teacher or the aide. Not Rose.
Rose's room. Rose says don't touch my American Girl doll because I styled her hair just the way I like it and it took a long time. Your daughter thinks the hair is just awful and Rose has invented the ugliest hair style ever. But who's in charge? Rose. It's her doll.
So, help your daughter see the bigger picture. Rose says to ignore Heather. But you, her own mother, has told her to play nicely with everyone. So whose rules are to be followed? Yours. Not Rose's.
It's that kind of critical thinking, learning to evaluate the situation, that if mastered, will prevent a lot of problems in the future. Should I say yes to this boy because he's pressuring me even though I know my priest/parents/self all say no? Should I try this pill because the head cheerleader says it will finally make me peppy enough to make the team, even though my self/doctor/parents have told me to refuse other people's medications or pills I'm not sure about? Should I cheat on the test even though I know it's wrong and the teacher said to keep your eyes on your own paper and do your own work?
So tell your daughter that Rose can make the rules about things that Rose owns (dolls, bike, etc) and that should be respected. When your daughter is playing in someone's yard or house, the mommy or daddy or grandma is in charge. At school, the teacher/principal/playground supervisor is in charge and their rules are to be followed. When she's just in the neighborhood, maybe chalk drawing on the sidewalk or skipping down the street, your family rules are in charge. Your family rules are: be polite to everyone, don't leave people out, be safe and wear your helmet, don't go further than that street sign or the park or whatever. When she gets older, your daughter will have the ability to clearly evaluate a situation and not be pressured, and will develop a good moral and ethical point-of-view. Eventually, your family's good rules will become her own and she'll be able to make good decisions.
I wouldn't speak to any teacher, and I wouldn't just leave it up to your daughter's discretion. I'd start building a firm foundation within her now, giving her clear guidance since she's only three, role-playing, using simple language. You really can't expect her to have developed a great deal of empathy or social awareness at 3, although this is the time when that kind of stuff starts to sink in. "Oh, so that's why Billy cried. I called him a bad name and even though I didn't hit him, it made him feel sad". For now, help her formulate a perspective that will last for her whole life.