WASHINGTON – President Trump i s tightening the noose on Iran and summoned his top military commander to signal to Tehran that it’s time to make a deal. CENTCOM Commander Adm. Brad Cooper is reportedly briefing Trump Thursday about military strategy, but experts tell The Post there was a bigger message at play. “It was a signal to Iran and a political trial balloon to the US,” a former administration official said. That signal: Tehran should come to the table and make a peace deal or face more