// Test toSuggestItem when tags and roles are null (converted to empty lists)
        String word = "null tags and roles";
        float boost = 1.0f;
        List<String> readings = Arrays.asList("reading1");
        List<String> fields = Arrays.asList("field1");

        elevateWord = new ElevateWord(word, boost, readings, fields, null, null);
        SuggestItem suggestItem = elevateWord.toSuggestItem();