CEDAR RAPIDS — “Trailblazing,” glass-ceiling-breaking Democratic activist and social service pioneer Jean Oxley has died, her family said Sunday. She was 94.Oxley was the first woman ever elected to the Linn County Board of Supervisors, missing being the first female supervisor in the state by a couple of years. She became the longest-serving Linn County supervisor, on the board for 24 years from 1972 to 1996 and earning a reputation as a champion for the elderly, young and disabled.Linn County’s administrative building at 930 First St.