On most tiny tropical islands, the activities for the day predictable: snorkeling, diving, a spot of swimming, and cocktails served in coconut shells. If that’s all you require, the non-stop action at Club Med Kani in the Maldives can feel rather disconcerting. I was dubious about the enforced jollity of zumba classes, aqua-aerobics, sunset yoga, cookery lessons, a stage show every evening, and even a disco until the early morning hours. But on the second …