By Mark Felsenthal and Edwin Chan WASHINGTON D.C./SAN FRANCISCO (Reuters) – The U.S. chief technology officer at the time of the troubled rollout of Healthcare.gov is stepping down and moving into a new role recruiting top Silicon Valley talent to government, a source familiar with the situation said on Friday. Todd Park, a successful tech entrepreneur who became a top adviser to President Barack Obama, will move to the West Coast at the end of the month as part of a White House team, the source said on condition of anonymity because it has not been made public. The move signals a growing effort by the government to try to recruit from Silicon Valley.