South Korean stocks closed higher Friday, extending their winning streak to a second consecutive session, as semiconductor shares rallied following overnight gains on Wall Street. The local currency gained ground against the US dollar. After choppy trading, the benchmark Korea Composite Stock Price Index added 184.03 points, or 2.52 percent, to close at 7,475.94. Trade volume was moderate at 449.53 million shares worth 31.16 trillion won ($20.73 billion), with gainers far outnumbering losers 799