It was a busy evening at Nick’s Cove just before sunset on Sunday. Caitlin Sandberg was standing under the dim lights, chatting with her co-workers and attending to customers when she and the rest of the staff saw the smoke. Gasps erupted in the dining room as black clouds billowed from the chimney of the boat shack. As patrons watched with horror from the window, four staffers rushed out with fire extinguishers. But by the…