A troubled man who railed against Mayor Eric Adams and made bizarre, threatening rants on YouTube has been identified as a person of interest — and now a suspect — in the savage Brooklyn subway attack that injured at least 23 people Tuesday morning, officials said. Frank James — who warned last month that he was “entering the danger zone” — rented a U-Haul van tied to the N train attack in Sunset Park and is being sought for questioning, police said at an evening briefing. “Mr. Mayor, I’m a victim of your mental health program,” James said in one...