The fun starts early in Beckett’s Endgame. Within minutes of opening his mouth, blind bully Hamm decides to starve his servant. ‘I’ll give you just enough to keep you from dying,’ he tells Clov. One biscuit and a half. Which feels positively lavish compared with what composer Gyorgy Kurtag feeds us musically in the first 20 minutes of his operatic adaptation (receiving its British première at the Proms).