KYIV, Ukraine — Ukrainian President Volodymyr Zelenskyy on Tuesday visited an eastern city that is a focus of some of the most intense combat of Russia’s nearly 10-month war, while Russian President Vladimir Putin praised the “courage and self-denial” of his front-line forces in Ukraine. Zelenskyy met with military personnel in Bakhmut, the scene of “fierce battles” between Ukraine’s defenders and Russia’s invading forces, the president’s office said. The city, located about 600 kilometers (380 miles) east of Kyiv, has remained in Ukrainian hands, thwarting Moscow’s goal of capturing Ukraine’s entire Donbas region.