Neighbors play dominoes during a power cut in Havana on July 5, 2026. Shipping containers stranded in various Caribbean ports include humanitarian aid to Cuba ranging from solar panels to medication to colostomy bags. (Lisette Poole González/The New York Times) By ED AUGUSTIN and FRANCES ROBLES Thousands of containers filled with food, medicine and other goods bound for Cuba have been stranded throughout the Caribbean since two shipping giants stopped deliveries to avoid tough U.S. sanctions,…