Maybe it’s the giant crab. If you’ve been to Gaido’s, or just driven past the building at Thirty-Ninth and Seawall, in Galveston, you know the crab. Twelve feet wide and anatomically correct, the gargantuan crustacean atop the roof has awed children for decades. I was one of them. I’m a BOI (“Born on Island”), and that blue crab was as big a part of my childhood food memories as braving my first raw oyster. (It was around the same time my mother, raised in Harlingen, got me to try the menudo she always ordered at La Galvestonia.) My version of a cornucopia was the Gaido’s Gulf oyster platter, with its bounty of bivalves fried, grilled, and seared with bacon. Gaido’s opened in 1911 and quickly established a reputation…