NEW YORK — Saturday’s game at Barclays Center offered another glimpse at what this Nets team can be when engrossed at both ends of the court — at least through three quarters. While Jacque Vaughn’s team won 106-104 in a game that they never trailed, they are still struggling to close out opponents. Their matchup against the Houston Rockets had no business being as close as it was late. Cam Thomas, who received his first start since Dec. 27 in place of Cam Johnson, was the player who ignited the fuse for Brooklyn on offense. He started 5 for 6 from the field and finished with a game-high 37 poi…