Dishcraft Robotics Inc., a startup that delivers clean dishes daily to big commercial kitchens, raised $20 million in new funding to help it begin offering reusable to-go containers aimed at filling a growing need caused by the Covid-19 pandemic. The San Carlos company uses a robotic washing system to clean thousands of dirty dishes a day that it picked up at corporate cafeterias, school campuses, caterers and large restaurants before the coronavirus crisis.