By Jonathan Landay WASHINGTON (Reuters) – A declassified U.S. intelligence report assessed that the Ukraine war has cost Russia 315,000 dead and injured troops, or nearly 90% of the personnel it had when the conflict began, a source familiar with the intelligence said on Tuesday. The report also assessed that Moscow’s losses in personnel and armored vehicles to Ukraine’s military have set back Russia’s military modernization by 18 years, the source said. The Russian embassy did not immediately respond to a request for comment. Russian defense ministry and Kremlin officials could not immediatel…