University of Chicago Law School will spend its 2015-16 school year under the stewardship of a familiar face: Geoffrey R. Stone.A law school faculty member since 1973, Stone was named interim dean on Friday, effective July 1.“I thought about it and decided that I have a responsibility to the institution,” said Stone, who agreed to serve after being recommended by faculty members and appointed by President Robert J. Zimmer and Provost Eric D. Isaacs.Neither Zimmer nor Isaacs could be reached for comment.&ldquo …