Add a qmllint rule to detect when alias properties point to objects with custom properties that can't be accessed via grouped property syntax. See original discussion: https://bugreports.qt.io/browse/QTBUG-66632

Current warning: Cannot assign to non-existent property "restingY"

// Eye.qml
Item {
    property alias pupil: pupil
    
    Item {
        id: pupil
        property int restingY  // Custom property on unnamed type
    }
}

// main.qml  
Eye {
    pupil.restingY: 20  // This should trigger lint warning
}

Now this is confusing because the property is right there.