WASHINGTON — President Trump was stunned to learn last week that US intelligence indicates new Iranian Supreme Leader Mojtaba Khamenei may be gay — and that his father, the late Ayatollah Ali Khamenei, feared his suitability to rule the Islamic Republic for that reason, The Post can reveal. Trump couldn’t contain his surprise and laughed aloud when he was briefed on the intel, according to sources. Others in the room also found it “hilarious” and joined the president’s reaction, while one senior intelligence official “has not stopped laughing about it for days,” said one person familiar with the briefing.