A former appointee of Minnesota Gov. Tim Walz is being sought in connection with the assassination of a state lawmaker and the shooting of another, police sources said. Vance Luther Boelter allegedly posed as a police officer when he shot Sen. John Hoffman and his wife in their Champlin home early Saturday, leaving them seriously injured before moving on to former Democratic House Speaker Melissa Hortman’s house — where he is believed to have slaughtered her and her husband, sources told The Post. Boelter, 57, was appointed by Walz in 2019 to serve a four year stint on the Governor’s...