WASHINGTON—America’s unemployment rate tumbled last month to its lowest point since the pandemic struck, even as employers appeared to slow their hiring—a mixed picture that pointed to a resilient economy that’s putting more people to work. The government reported Friday that businesses and other employers added just 210,000 jobs in November, the weakest monthly gain in nearly a year and less than half of October’s increase of 546,000. But other data from the Labor Department’s report painted a brighter picture. The unemployment rate plummeted from 4.6 percent to 4.2 percent as a substantial 1.1 million Americans said they found jobs last month. The U.S. economy still remains under threat from a spike in inflation, shortages of labor and supplies, and the potential impact of the Omicron variant of the coronavirus. But for now, Americans are spending freely, and the economy is forecast to expand at a 7 percent annual rate …