LONDON — Keir Starmer knows the war in Iran could sink his number one domestic mission: Cutting the cost of living.  But unfortunately for him, the man with most power to stop the conflict seems not to be in a hurry.  The U.K. prime minister was more explicit than ever on Wednesday that he wants to see “de-escalation” in the Middle East — in part because it’s the surest way of stopping energy bills skyrocketing in his own country.  Starmer said his government was “working around the clock” to