First of all - love the name! Noah is one of my favorite girl names! We are naming our daughter Micah

Anyways...
My cousin adopted a boy who has a rather severe peanut allergy, but for the most part he is able to live a very normal childhood. Elementary (or Primary) schools are usually pretty great about making special accommodations for children with different needs.
She'll have to be a bit more careful about the foods she comes in contact with - but she shouldn't have to be segregated from her classmates during lunchtime. Pistachio nuts aren't crazy common in other foods, which is a positive here. I think the best thing is to educate Noah and her teachers the best you can - this way, when you're not able to be with her, she can better recognize foods that may be potentially harmful to her. Knowledge is power!