The presidents of Ecuador, Ivory Coast, Kenya and Somalia will join many Western heads of state and government and other leaders at a conference this weekend aimed to plot out first steps toward peace in Ukraine – with Russia notably absent. Some 100 delegations including European bodies and the United Nations will be on hand at the Bürgenstock resort overlooking Lake Lucerne. Who will show up – and who will not – has become one of the key stakes of a meeting that critics say will be useless without the presence of Russian President Vladimir Putin’s government, which invaded Ukraine in Februar…