The Prime Minister Gordon Brown is on a collision course with Prince Charles over the sensitive issue of the Chinese government's human-rights record. The exiled Tibetan spiritual leader, the Dalai Lama, is planning to visit Britain in May and has requested a meeting with the Prime Minister. But Mr. Brown, keen to boost trade links with China, has yet to reply to the request and risks being embarrassed during the trip by the Prince of Wales, a long-standing friend of the Tibetan