Taiwan’s defense ministry issued an urgent alert Tuesday about a Chinese satellite launched on a rocket flying over the island, an alarming message that interrupted the final days of campaigning before a major election and spurred accusations of a political ploy. The alert was sent to mobile phones across the island of 23 million people, where presidential and legislative assembly elections will be held Saturday. In English, the initial alert cautioned there was a missile flyover — an error quickly corrected by Taiwanese officials. “It was a satellite, not a…