Provide option for saving Qml Canvas to a QImage

At the moment we can save Qml Canvas only to a data buffer or to a file (https://doc.qt.io/qt-6/qml-qtquick-canvas.html#save-method).
A method which allows to save the canvas to a QImage would be useful. This could be implemented similar to the grabToImage function: https://doc.qt.io/qt-5/qml-qtquick-item.html#grabToImage-method