By Joseph McBride The San Francisco 49ers have signed Joshua Dobbs as backup quarterback for star player Brock Purdy, taking over from Sam Darnold. Dobbs, who was drafted by the Pittsburgh Steelers in 2017, has moved nine times without staying with a team for longer than a year since leaving his first franchise. Dobbs offers plenty of experience, despite just 14 career starts. His time with different coaches and quarterbacks around the league, and his remarkable ability to adapt quickly to his surroundings and learn the playbook make him an ideal number two. His journey through the 2023 season…