Perched on the edge of West Africa, Senegal has long gone quietly about its business while its neighbors get into all sorts of trouble. Quietly, of course, is a misleading word in the context of Dakar, the sultry capital city and dust-ridden domain of all-night music clubs, infamous traffic, relentless hustlers, and nonstop construction, where the dead silence of night is regularly punctured by soaring muezzin calls to…