The “Valve answered in 24 hours” story everyone is sharing has the timeline backwards. And the same thing happened in 2018. Here's how this week actually went. Epic spent almost a year rebuilding its game launcher, then paid an outside testing firm called Keywords Studios to run it against Steam on 13 Windows PCs. Epic's app got from a cold start to the store page in 5.47 seconds on average. Steam took 10.07. Those numbers were legit when Epic ran them. But on October 13, Valve put out a…