San Francisco prosecutors filed various charges Wednesday against a 43-year-old woman in connection with a series of attacks on Polk Street that one victim says may have been racially motivated.Emmi Lopez, a transgender woman who is listed in court records as Michael A. Lopez, is facing assault, battery and other charges after police arrested her in the string of incidents Monday morning near Polk and Clay streets that involved three Asian victims. ... While police booked Lopez on suspicion of a hate crime, the District Attorney’s Office has not filed hate crime charges against her, citing the need for further...