NEW YORK — When James Harden came, the mission stayed the same. And now that he’s gone, the show must go on. The answer to Steve Nash’s season-long roster experiment has been before his eyes this entire time, and it’s why the Nets are confident their Barclays Center-shaped ship is still sturdy. The dark clouds have parted in the aftermath of Hurricane Harden, and Nets GM Sean Marks has plugged the holes in this vessel’s deck. His team might be riding a league-worst 10-game losing streak, and it certainly just traded its best available player for three complementary puzzle pieces. In dealing Ha…
