NEW YORK — Two weeks shy of a year after abruptly quitting Fox News Channel with a declaration that “truth will always matter,” Shepard Smith returns to television this week at his unexpected new home. He begins a general interest nightly newscast Wednesday at 7 p.m. on the financial network CNBC, putting him back in the time slot he loved before Fox moved him to the afternoon seven years ago. The 56-year-old newsman, a Fox News original who joined that network at its start in 1996, says he’s relishing the fresh start. “We’re going to come out and do just the news,” he said.