The unlikely presidential run of Andrew Yang, who is proposing a $1,000-a-month “freedom dividend” to every adult in America, rolled Friday into San Francisco, where some 3,000 supporters listened to the New York tech entrepreneur warn about how artificial intelligence and robotics are taking jobs. The 44-year-old son of Taiwanese immigrants who met each other at UC Berkeley has already surpassed expectations — virtually nonexistent when he got into the race — by inspiring enough donations to qualify for the Democratic primary debate in June.