New Yorkers are fortifying their homes with panic rooms and bullet-proof doors like never before over fears about crime, migrants and national turmoil — and it’s not just the city’s elite partaking in the trend. “Not every [customer] is an ultra-rich stockbroker — a lot of them are just people, middle-class kind of people,” said Steve Humble, founder of the home-defense contractor Creative Home Engineering. “I’d say the pandemic really kicked off an uptick. Business was really good throughout the pandemic time, and it really hasn’t slowed down,” said Humble, who specializes in top-of-the-line secret doors disguised as bookshelves, fireplaces,...