Abby Rosebrock is a different kind of triple threat. As a playwright, she brings an invigorating new voice to the stage with the debut of her comedy-drama Dido of Idaho, at the Ensemble Studio Theatre. As an actor in her own play, portraying a former beauty pageant contestant in crisis, her comic timing is precise. And as a practitioner of stage combat, “threat” is too gentle a word for her character who, when faced with a challenge to her domestic security, brandishes a razor-sharp pair of cuticle scissors.