The music series isn’t quite as time-honored as a Fourth of July parade, or even the Twilight Parade this week. It’s only been a tradition for about 25 years, bringing weekly live music to the downtown square, but it has turned into a major social event. Friends and neighbors gather at impromptu picnic spots beneath a palm or pine to share food, beverages (usually wine) and conversation, or to dance with abandon in front of the Gazebo stage.