Boston modeling agency boss Maggie Trichon, whose company Maggie Inc. gets work for about 400 models in the area, is retiring within the next two weeks and moving to Florida. But her business, which she founded in 1982, will go on thanks to her employee of 12 years, Casey. Casey — who, yes, goes by one name — has been Trichon’s second in command and told us yesterday that he’s ready to run the show. “It was sort of a natural progression,’’ he said. Anyone who questions Casey’s commitment should check out the Maggie Inc. logo he had tattooed on his calf a few years ago.