I would say she's dead, at least in the film adaptations.
She wasn't moving after being mauled Von Greyback. It says on the wiki that she could have possibly been hit Von a stunning curse, but that seems unlikely
It shows pavarti and Proffessor Trelawny sitting Weiter to a body which they've covered with a blanket. I assumed it was Lavender seeing that Pavarti was her best friend and she was one of Trelawney's best students.
I do believe that Lavender survived in the books. Her dying in the Filme was simply Yate's interpretation of the events.
In the book it says to bodys fell from a balcony that was greyback and lavender u see in the film lavender being eatend but in the book she is seen strugaling anf feble and in the film padma and trelwarney cover the body of padma's twin