Lia Cirio’s parents say she came out of the womb dancing. “I was always moving around,” she recalls. “I had the little tutu pajamas and all that stuff. But my core childhood memory is going to ‘The Nutcracker.’ All I wanted was to be Clara.” Cirio is Clara. She’s also Princess Aurora from “The Sleeping Beauty,” Odette from “Swan Lake,” Nikiya from “La Bayadère,” and all the roles she has danced and portrayed over the course of 22 years as one of Boston Ballet’s principal dancers.