ISTANBUL — A delegation from one of Turkey’s biggest pro-Kurdish political parties met a leading figure of the Kurdish movement in prison Saturday, the latest step in a tentative process to end the country’s 40-year conflict, the party said. Three senior figures from the Peoples’ Equality and Democracy Party (DEM) met the party’s former co-chairperson, Selahattin Demirtas, at Edirne prison near the Greek border. The meeting with Demirtas — jailed in 2016 on terrorism charges that most observers, including the European Court of Human Rights, have labelled politically motivated — took place two weeks after DEM members met Abdullah Ocalan