* Katakana string into a list of possible Alphabet readings. It uses a predefined mapping of Katakana
 * characters to their Alphabet equivalents, handling both single and double Katakana character combinations.
 * </p>
 *
 * <p>
 * The conversion process involves iterating through the input string, identifying Katakana characters,

 *   to be executed when the computation is complete.
 *   The Promise class has then and error methods that allow you to register callbacks
 *   for successful and unsuccessful computations, respectively.
 * </p>
 *
 * <p>
 *   The Deferred class uses a CountDownLatch to allow you to wait for the computation to complete.