Rarely is there a restaurant that encourages long nights spent lingering over good food in a no-rush atmosphere. Often, you’ll find yourself hastily pushed out of an establishment for the next reservation or given last calls for your kitchen order by 9pm. But what if you’re seeking the vibrant buzz of old-school New York — the kind of place Carrie Bradshaw might have frequented for a spontaneous late night? This summer, the newly opened Aquarelle restaurant offers the opportunity to…