Hedge funds have turned bullish on the yen for the first time since 2021, after big swings in the foreign exchange market led to a surge in a popular yen trade. Leveraged funds hold about $7 million worth of 86 contracts betting that the yen will appreciate, according to the latest data from the U.S. Commodity Futures Trading Commission (CFTC) for the week ending Aug. 13, and speculators in general are bracing for a rise in the yen, marking a sharp shift from the extremely negative sentiment tra...