NEW YORK — State Supreme Court Judge Juan Merchan cleared the courtroom Monday over a dramatic spat with the defense’s first main witness, Robert Costello , causing a period of mayhem at former President Donald Trump’s hush money trial. Mr. Costello , a lawyer who once spoke to Trump lawyer-turned-accuser Michael Cohen, seemed to take exception to one of Judge Merchan’s objection rulings, uttering “Jeez,” and then sighing, “Strike it.” Judge Merchan told the jury to leave for a moment. “You don’