The map is moving again. In Eastern Ukraine, after months of severe retreats, Vladimir Putin’s forces made their first significant advance: capturing the salt mine town of Soledar. It wasn’t, however, General Valery Gerasimov, the Kremlin’s military chief in Ukraine, who first rushed to claim victory — posing in a deep shaft — but Yevgeny Prigozhin, the boss and the angry face of the Russian mercenary group Wagner.