By Pavel Polityuk and Vitalii Hnidyi KYIV/KHARKIV, Ukraine (Reuters) -Ukraine’s President Volodymyr Zelenskiy on Wednesday hailed the European Union’s expected offer of candidate status for his battle-weary nation as Russian forces pounded Ukraine’s second biggest city Kharkiv and the eastern Donbas region. European leaders will formally set Ukraine on the long road to EU membership at a summit in Brussels on Thursday. Though mainly symbolic, the move will help lift national morale at a very difficult time in a four-month conflict that has killed thousands, displaced millions and flattened tow…