Beauty Reigns Supreme in a Florida Enclave
South Beach, southernmost tip of city of Miami Beach, is magnet for beautiful people; South Beach is utterly absorbed by beauty, peopled with fashion models and dreamers; area draws beautiful people of all colors and sexual orientations to its pastel Art Deco hotels, emerald ocean and chic, throbbing nightclubs where unpretty, uncool and unfashionable are unwelcome; photos (M)