He’s gone. Rest in peace to Jerry Garcia, a key figure on the San Francisco scene for nearly three decades, who passed away 15 years ago today. On April 12th, 1993, he, Bob Weir and Vince Welnick nailed the national anthem at Candlestick Park, before the San Francisco Giants’ season home opener. Then-Giants manager Dusty Baker grins, the crowd goes wild, and I’m proud to be an American…