There is a particular kind of dark that falls over a football stadium once the sun has gone down and the lights have snapped on above it, a dark that has nothing to do with the hour and everything to do with expectation. It does not care that the calendar still reads August. It does not care that the only score being kept is between the ones and the twos, or that the games that count are still three weeks off with Oregon State waiting on the other side of the opener. Thursday night, under a sky gone the color of a fresh bruise, the University of Houston turned the lights on for a fall camp…