“ Annette ” is a film that’s likely best experienced rather than described.Anyone familiar with the work of French director Leos Carax, best known for the surreal Denis Lavant fantasy “Holy Motors,” probably already knew that. But tack on the fact that the script and music was written by Sparks duo Ron and Russell Mael, known for their sophisticated, theatrical and irreverent songs, and “Annette,” starring Adam Driver and Marion Cotillard, adds up to something that defies explanation.