By Anna Voitenko and Tom Balmforth CHASIV YAR, Ukraine/KYIV (Reuters) – Rescuers pulled survivors on Monday from an apartment block destroyed by a Russian missile strike that killed 31 people in eastern Ukraine, President Volodymyr Zelenskiy said while lamenting Moscow’s firepower advantage despite billions in Western aid. The civilian deaths hammered home the human cost of Russia’s invasion, now in its fifth month, as Russian President Vladimir Putin’s forces push to capture all of Ukraine’s industrial Donbas region after declaring victory in one of its two provinces this month. In the city o…