PUN POWER: Meanwhile, over on I-5, the latest weapon against congestion is a jar of Knott’s boysenberry jam. . . . At the transit district’s request, Knott’s donated 600 1.3-ounce jars, which were relabeled “I-5 Traffic Jam” and sent them to transportation coordinators at the county’s larger companies. “Help the I-5 out of a jam. Rideshare,” says the accompanying card. . . . The idea is to promote the district’s new offer of free gasoline to I-5 car-poolers, and initial reaction has been good, a spokeswoman says.