error: ninja: build stopped: subcommand failed.

[qcoderpro]

This is my example (Qt 6.4.3)
main.qml:

import QtQuick
DocumentQML { visible: true }

DocumentQML.qml:

import QtQuick
import QtQuick.Controls
import Qt.labs.platform as NativeDialog

ApplicationWindow {
    id: root
    title: (fileName.length === 0 ? "Document" : filename) + isDirty ? "*" : ""
    width: 800
    height: 600

    property bool isDirty: true
    property string fileName
    property bool tryingToClose: false

    menuBar: MenuBar {
           Menu {
               title: qsTr("&File")
               MenuItem {
                   text: qsTr("&New")
                   icon.name: "document-new"
                   onTriggered: root.newDocument()
               }
               MenuSeparator {}
               MenuItem {
                   text: qsTr("&Open")
                   icon.name: "document-open"
                   onTriggered: openDocument()
               }
               MenuItem {
                   text: qsTr("&Save")
                   icon.name: "document-save"
                   onTriggered: saveDocument()
               }
               MenuItem {
                   text: qsTr("Save &As...")
                   icon.name: "document-save-as"
                   onTriggered: saveAsDocument()
               }
           }
       }


    function createNewDocument() {
        var component = Qt.createComponent("DocumentWindow.qml");
        var window = component.createObject();
        return window;
    }

    function NewDocument() {
        var window = createNewDocument();
        window.show();
    }

    function openDocument() {
        openDialog.open();
    }

    function saveAsDocument() {
        saveAsDialog.open();
    }

    function saveDocument() {
        if(fileName.length === 0)
            root.saveAsDocument();
        else {
             // Save document here
            console.log("Saving document")
            root.isDirty = false;

            if(root.tryingToClose)
                root.close();
        }
    }

    NativeDialog.FileDialog {
        id: openDialog
        title: "Open"
        folder: NativeDialog.StandardButton.writableLocation(
                    NativeDialog.StandardPaths.DocumentsLocation)
        onAccepted: {
            var window = root.createNewDocument();
            window.fileName = openDialog.file();
            window.show();
        }
    }
    NativeDialog.FileDialog {
        id:saveAsDialog
        title: "Save as"
        folder: NativeDialog.StandardPaths.writableLocation(
                    NativeDialog.StandardPaths.DocumentsLocation)

        onAccepted : {
            root.fileName = saveAsDialog.file
            saveDocument();
        }
        onRejected: root.tryingToClose = false;
    }



    onClosing: if(root.isDirty) {
            closeWarningDialog.open();
            close.accepted = false;
        }

    NativeDialog.MessageDialog {
        id: closeWarningDialog
        title: "Cloasing document"
        text: "You have unsaved changes. Do you want to save your changes?"
        buttons: NativeDialog.MessageDialog.Yes | NativeDialog.MessageDialog.No
        | NativeDialog.MessageDialog.Cancel

        onYesClicked: {
            // Attempt to save the document
            root.tryingToClose = true
            root.saveDocument();
        }
        onNoClicked: {
            // Close the window
            root.isDirty = false
            root.close()
        }

        onReject: {/* do nothing */ }
    }
}

CMakeLists.txt:

cmake_minimum_required(VERSION 3.16)

project(QML_3 VERSION 0.1 LANGUAGES CXX)

set(CMAKE_CXX_STANDARD_REQUIRED ON)

find_package(Qt6 6.5 REQUIRED COMPONENTS Quick)

qt_standard_project_setup(REQUIRES 6.5)

qt_add_executable(appQML_3
    main.cpp
)

qt_add_qml_module(appQML_3
    URI QML_3
    VERSION 1.0
    QML_FILES Main.qml
    DocumentQML.qml
)

set_target_properties(appQML_3 PROPERTIES
    MACOSX_BUNDLE_GUI_IDENTIFIER my.example.com
    MACOSX_BUNDLE_BUNDLE_VERSION ${PROJECT_VERSION}
    MACOSX_BUNDLE_SHORT_VERSION_STRING ${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}
    MACOSX_BUNDLE TRUE
    WIN32_EXECUTABLE TRUE
)

target_link_libraries(appQML_3
    PRIVATE Qt6::Quick
)

install(TARGETS appQML_3
    BUNDLE DESTINATION .
    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
)

When run, I get this error:
error: ninja: build stopped: subcommand failed.