DALLAS — Perhaps no one has more closely followed Luka Doncic’s NBA trajectory than Orlando coach Jamahl Mosley, who as a Mavericks assistant was Doncic’s primary developmental coach during his first three seasons. “That’s my guy,” Doncic said after bantering with Mosley through much of Dallas’ Sunday night win over the Magic. Mosley said he’s noticed two subtle differences in Doncic this…