A shift to technology stocks by China’s most seasoned fund managers has backfired, with the unwinding of AI plays taking a toll on the performances of their products.Funds run by some star managers with a value-investing approach all recorded declines in net asset values last month after they switched to chipmakers and the manufacturers of optical transceivers and out of long-held consumer bets in the second quarter. Technology stocks listed in mainland China suffered their biggest monthly declines in July, aligning with a global unravelling of artificial intelligence bets amid doubts about the investment returns on cloud-service infrastructure.The pursuit of…