}

    public void test_convertModernKatakana_Tse() {
        List<String> results = converter.convert("ツェ", null);
        assertTrue(results.contains("tse"));
    }

    public void test_convertFyu_BugFix() {
        // Test that フュ correctly maps to "fyu" only (not "hyu")
        List<String> results = converter.convert("フュ", null);
        assertTrue(results.contains("fyu"));