Medical marijuana advocates and government representatives hammered out the final details of proposed new rules that would give Colorado the most comprehensive seed-to-sale cannabis business regulations in the nation. The rules would govern everything: how state officials regulate marijuana cultivation; how dispensary owners keep track of their sales; what makers of marijuana-infused pastries should put on their labels. Several of the rules would place Colorado in unprecedented territory — for instance, requiring marijuana growers to install security cameras through which state auditors could remotely monitor their crop.