Show quality chooser for JXL (JPEG XL) format

app/gvcore.cpp

@@ -128,6 +128,7 @@ struct GvCorePrivate
         QObject::connect(fileWidget, &KFileWidget::filterChanged,
                          JPEGQualityChooserWidget, [=](const QString &filter) {
             JPEGQualityChooserWidget->setVisible(filter.contains(QLatin1String("jpeg")) ||
+                                                 filter.contains(QLatin1String("jxl"))  ||
                                                  filter.contains(QLatin1String("webp")) ||
                                                  filter.contains(QLatin1String("avif")) ||
                                                  filter.contains(QLatin1String("heif")) ||

lib/document/documentloadedimpl.cpp

@@ -84,6 +84,7 @@ bool DocumentLoadedImpl::saveInternal(QIODevice* device, const QByteArray& forma
     QImageWriter writer(device, format);
     // If we're saving a non-JPEG image as a JPEG, respect the quality setting
     if (format == QByteArrayLiteral("jpeg") ||
+        format == QByteArrayLiteral("jxl")  ||
         format == QByteArrayLiteral("webp") ||
         format == QByteArrayLiteral("avif") ||
         format == QByteArrayLiteral("heif") ||