By Gleb Garanich and Natalia Zinets BUCHA/LVIV, Ukraine (Reuters) – Moscow signaled on Friday it was scaling back its ambitions in Ukraine to focus on territory claimed by Russian-backed separatists as Ukrainian forces went on the offensive, recapturing territory on the outskirts of the capital Kyiv. In the first big sign that Western sanctions on Russia were impacting investment from China, sources told Reuters state-run Sinopec Group, Asia’s biggest oil refiner, had suspended talks on a petrochemical investment and a venture to market Russian gas. In the month since they launched their invas…