SARAJEVO, Bosnia-Herzegovina (AP) — European Council President António Costa said Monday that this week’s European Union summit with Western Balkan candidate nations aims to show that the opportunity for enlargement is real. Speaking in Bosnia at the start of a pre-summit tour of the Western Balkans, Costa said that amid global geopolitical uncertainty and economic instability, “enlargement is a geostrategic interest for Europe .” “It (enlargement) is an investment in the peace, stability and