On Tuesday, a Florida judge informed two lawyers representing former President Donald Trump, neither of them licensed in the state, that they had bungled routine paperwork to take part in a suit filed after the FBI’s search this month of Trump’s Mar-a-Lago home and private club. Trump has projected his usual bravado, and raised millions of dollars online from outraged supporters, since federal agents descended on the property more than two weeks ago and carted off box loads of material including highly classified documents. But something is different this time — and the errant court filing offered a glimpse into...