(Reuters) – Russian domestic tech companies, led by entities controlled or associated with state-owned gas giant Gazprom, are pouncing on the blockade and exodus of foreign internet firms, sensing opportunities in Russia’s growing digital isolation. Russia has restricted access to Twitter and Meta Platforms’ flagships Facebook and Instagram since sending thousands of troops into Ukraine on Feb. 24, as the country’s long-simmering dispute with Big Tech escalates into a battle to control information flows. The digital exodus provoked by Western sanctions, and a clampdown by Russian media regulat…