BISMARCK, N.D. — When lawmakers filed into the Capitol here in August, they were repeating a familiar scene. North Dakota was in the throes of an oil bust after a six-year drilling boom that transformed parts of the state. The price of oil had been in free fall, state revenue was down almost one-fourth and the state's primary savings account was almost empty. Now the lawmakers had assembled for a three-day special session to decide the winners and losers. It could have happened in any state capitol in the oil patch, in any of the downturns that have plagued the oil business since its inception. But this oil bust could be different.