default <S2 extends Suggestion> @NonNull SuggestionFactory<C, S2> mapped(final @NonNull SuggestionMapper<S2> mapper) {
        return new MappingSuggestionFactory<>(this, mapper);
    }
Returns a new suggestion factory that maps the results of {@code this} factory to the type {@link S2} using the
given {@code mapper}.

@param <S2>   the new suggestion type
@param mapper the suggestion mapper
@return the mapped factory
cloud-core/src/main/java/org/incendo/cloud/suggestion/SuggestionFactory.java