Boston Burger Company will launch a food truck within the next few weeks. Owner Paul Malvone admits that while cooking up his full roster of 28 burgers is difficult on wheels, he’ll offer seven burgers a day. “We’ll have our staples,” he says. “The hot mess, the mac attack, and a few other daily specials.” He’s also considering a third restaurant location at 1105 Massachusetts Ave. in Cambridge, between Harvard and Central squares. There are currently branches in Somerville and in Boston.