The Feb. 10 NBA trade deadline is less than a month away and wafts of rumors are in the air, though most actual negotiations won’t begin to percolate until February. So, Nico Harrison, would you say trade season has been more or less active than usual? “So how busy is it?” the Mavericks’ first-year president and general manager asked, rhetorically, adding with a smile: “I don’t know because this is my first time, so I have nothing to compare it with.”