By Michel Rose and Dmitry Antonov MOSCOW (Reuters) -French President Emmanuel Macron, the top Western leader to visit Moscow since Russia began massing troops on the border with Ukraine, told Vladimir Putin at the start of talks in the Kremlin on Monday that he aimed to avoid war and build trust. Macron, who is expected to seek re-election in April, has positioned himself as a potential mediator on Ukraine with Paris voicing scepticism about predictions by Washington, London and other Western capitals that a Russian assault is imminent. Macron told the Russian president he was seeking a “usefu…