Shawn Ryan, the creator and visionary behind FX’s “The Shield” -- easily the grittiest, edgiest and most shocking police series to hit TV when it debuted in 2002 -- bears an uncanny resemblance to the series’ lead character, Det. Vic Mackey (Michael Chiklis): both are bald and imposing, both are mavericks who have succeeded by doing things their own way, and Ryan’s wife Cathy Cahlin Ryan even plays Mackey’s wife, Corrine. But it’s there that the similarities likely end. Tough corrupt cop Mackey can declare the street as a major influence, where Ryan cites playwright David Mamet, with whom