Describing a summer on the beaches characterized by few serious mishaps, a lack of unruly crowds, and no extreme weather, Ed McDonald, the East Hampton Village beach manager, said, “Dull is good,” as he summarized the season’s activities and revenue at a village board meeting Friday. He noted that no one had drowned and said the Main Beach lifeguards, led by Eric Bramoff, deftly and professionally handled two incidents in which bathers suffered neck injuries.