TOKYO — The three new missiles North Korean leader Kim Jong Un has tested over the past week are eerily familiar to military experts: They look just like a controversial and widely copied missile the Russian military has deployed to Syria and has been actively trying to sell abroad for years. Ending a pause in ballistic missile launches that began in late 2017, and alarming North Korea’s neighbors, Kim personally supervised the launch of the first missile from the country’s east coast Saturday and two more from the west Thursday.