SAN DIEGO — Stephan Jaeger eagled his final hole Thursday on the North Course at Torrey Pines, giving him a 64 for a one-shot lead midway through the Farmers Insurance Open. Jaeger, who began the day 4-under after an opening-round 68 on the South, started on the North’s back nine and birdied five holes to move onto the leaderboard. The 34-year-old German, ranked No. 101 in the world, is looking for his first PGA Tour win. He was within a stroke of the lead when he stepped to the 556-yard, par-5 9th, took two shots to reach the right front edge of the green and then holed his eagle putt. “Had a…