Tesla Inc. reported a surprise record quarter of vehicle sales as US consumers accelerated electric-car purchases before federal tax credits expired.The company delivered 497,099 vehicles worldwide, 7.4% more than a year ago. While that total far exceeds the roughly 439,600 average analyst estimate compiled by Bloomberg, Tesla’s shares slumped Thursday following a record monthly gain in market capitalization.A rush to take advantage of a $7,500 tax credit for EV purchases delivered a temporary boost to Tesl ...