By Anton Zverev DONETSK, Ukraine (Reuters) – Politicians and military sources in Russian-backed breakaway regions of eastern Ukraine say they do not see an imminent risk of full-scale war while attempts are still under way to find a diplomatic solution. A long-simmering conflict between the Russian-backed separatists and the Ukrainian army is part of a deeper crisis between the two countries in which Russia has massed more than 100,000 troops near Ukraine’s borders, prompting U.S. warnings of a possible attack within days or weeks. Andrei Purgin, a local politician and former separatist leader…