Sunday was friendly. At four in the afternoon, the Viking Starship returned to Montauk Harbor after a long day on a calm sea — cold, but calm and mostly sunny. Capt. Carl Forsberg smiled down from the Starship’s wheelhouse at the 80 booted, knit-hatted, and well-bundled anglers departing with coolers stocked with cod fillets. They had the look of a day well spent.