CAIN BURDEAU One hundred days ago, Russian President Vladimir Putin launched a full-scale invasion of Ukraine. Now much of the vast country in Eastern Europe lies in ruins, thousands of civilians and soldiers have been killed and the world’s superpowers are engaged in a perilous global struggle. (CN) — Friday marked the 100th day since Russian President Vladimir Putin ordered a massive invasion of Ukraine in February and upended world politics by launching a major war in Europe and turning his country definitively away from the West. Intense and bloody fighting continued…