This MR ensures that delegates created with make_shared do not also get
initialized with a QObject parent. Some of the classes used the same
constructor parameter for HomeScreen and used it as a parent simultaneously. This was refactored
so that they are separated.
Currently delegates do not get deleted when removed from models. Due to
the complexity of drag state and other objects, we can't simply delete
the delegate when removed from the model because they might still be
involved in animations or other state at the time of removal. Use smart
pointers to have the delegate objects deleted instead.
QML unfortunately doesn't support QSharedPointer, so we need to expose raw pointers to it.
