Clear startup feedback if a window is activated by the Workspace
The xdg-activation token can be saved and checked later if the window is not mapped yet.
If the activated window and the activation tokens have matching app ids, it will work as expected. However, if the app ids mismatch, the startup feedback won't be cleared (even though it should be).
This change makes the XdgActivationV1Integration monitor new windows and clear startup feedbacks as needed.