Russia’s army on Thursday launched a massive attack on Ukraine’s energy sector, forcing emergency power outages as temperatures dropped to freezing across the country.Ukraine’s energy grid has been heavily targeted since Russia invaded in February 2022, with Kyiv accusing Moscow of “terror” tactics by trying to plunge Ukrainian cities into darkness and cut off heating to civilians throughout the winter.The overnight strikes come after two weeks of dramatic escalation that has seen both sides launch new weapons to gain an upper hand ahead of Donald Trump being inaugurated as US president in…