KYIV, Ukraine — A Russia-appointed official in Ukraine's occupied Luhansk region said Monday that Moscow's forces have overrun all of it — one of four regions Russia illegally annexed from Ukraine in September 2022 despite not fully controlling a single one. If confirmed, that would make Luhansk the first Ukrainian region fully occupied by Russia after more than three years of war and as recent U.S.-led international peace efforts have failed to make progress on halting the fighting. Russian