SALEM, Ore. — To the beat of electronic dance music, men and women inside a slate-gray building harvested marijuana plants festooned with radio-frequency identification tags. In another room, an employee entered the tag numbers into a government database. The cannabis tracking system used by Avitas, a marijuana company with a production facility in Salem, is the backbone of Oregon’s regulatory system to ensure businesses with marijuana licenses obey the rules and don’t divert their product into the black market. A huge amount of data is entered into the system by Oregon’s 1,800 licensees every day, a reality that means the state has a tremendous amount of information at its fingertips.