How about this for perfect casting: has learned that Matthew McConaughey has been offered the role of Thomas Magnum in Universal Pictures’ adaptation of Magnum P.I., based on the successful ’80s television show that starred Tom Selleck. The character, a former Navy Seal turned reluctant detective, seems a sweet match for the laid-back actor. McConaughey, we’re told, is reading the script from writer/director Rawson Thurber (Dodgeball) and will decide shortly. Now the burning questions: Will he grow a mustache for the role? And will our Hawaiian shirts suddenly be cool again? Developing …