Unwanted Attention for Korea
South Korean fianncial officials are waging sales blitz on investors in New York; team, led by Finance Min Kim Jin-Pyo, is trying to overcome effects of bad first quarter for economy caused in part by international concern over North Korea's nuclear weapons program; foreign direct investment was down 48 percent in first quarter from year earlier; Bank of Korea trims its outlook for economic growth in 2003 to 4.1 percent, well below 6.1 percent growth recorded last year; photos (M)