In today’s newsletter: Dulles’ new parking deck, Trump’s golden horses and fans at Commanders training camp. THE LATESTOne of the D.C. area’s biggest attractions may soon be a parking garage. But just to be on the safe side, the authority had drawn up plans for a new parking deck — with one-fifth the capacity of what Trump is pledging. With a garage that big, there’s likely to be “all kinds of issues with throughput of vehicles, wayfinding, ventilation and fire safety,” said local parking expert Bill Boyle. “There’s no precedent for building a parking deck this big.”