In the climax of France’s presidential campaign, centrist President Emmanuel Macron and far-right contender Marine Le Pen will meet on Wednesday evening in a one-on-one television debate that could prove decisive before Sunday’s runoff vote. Both candidates have carefully prepared for the highly scrutinized debate that’s expected to last more than two hours. Macron, 44, emerged ahead from the April 10 first round and is leading in opinion polls with a margin varying between 3 and 13 percentage points. But Le Pen, 53, has significantly narrowed the gap compared to the last presidential election…