Friday’s disappointing employment report did little to derail forecasts of strong growth this year but gave fresh ammunition to critics who complain the Bush administration has failed to achieve its chief economic goal — job creation. advertisement The unemployment rate fell in December to 5.7 percent, its lowest level in nearly a year – but only because 309,000 people dropped out of the labor force, according to government data. Employers added a scant 1,000 jobs last month, a barely perceptible number in an economy of 130 million workers and far short of the 127,000 net new jobs analysts had been...