NIZHNY TAGIL, Russia — In this city of smokestacks, where a sooty haze enshrouds avenues of metallurgical plants and factories, signs are piling up that Russia's economic crisis has metastasized, chipping away at the eight-year resurgence that has buoyed the Kremlin's swagger. At a sprawling metalworking enterprise, management has announced it will lay off all but 33 of its 1,225 workers. Other Nizhny Tagil…