LONDON — Britain has donated Storm Shadow cruise missiles to the Ukrainian air force in a move widely seen as a game changer in Kyiv’s ability to mount long-range strikes against invading Russian forces. The decision to hand over a quantity of the MBDA-built cruise missiles was announced by British Defense Secretary Ben Wallace in a May 11 statement to lawmakers here. “Storm Shadow is a long-range, conventional, precision-strike capability,” he said. “It compliments the long-range systems