By Ryan Woo and Ziyi Tang BEIJING (Reuters) – Cities in central China hastily drew up plans to isolate migrant workers fleeing to their hometowns from a vast assembly facility of iPhone maker Foxconn in COVID-hit Zhengzhou, fearing they could trigger coronavirus outbreaks. Zhengzhou, capital of central Henan province, reported 167 locally transmitted COVID-19 cases in the seven days to Oct. 29, up from 97 infections in the prior seven-day period. Apple supplier Foxconn, based in Taiwan, currently has about 200,000 workers at its Zhengzhou complex and has not disclosed the number of infected wo…