It’s been just over 100 days since D.C. Mayor Adrian Fenty took office (106 to be precise), and the WaPo’s David Nakamura took the opportunity to pen a lengthy profile of the impression Fenty has left on the city so far. Fenty, 36, the youngest chief executive in the District’s history, has set out to create a more engaged and responsive government. He was elected in a landslide on a pledge to replace the detached,…