Websocket reconnection ensure data got lost and then trigger reload

[ddelpiano]

Just discussed in the VFB sprint with Robbie, he is testing this closing the websocket and noticed that the reconnection is then associated to a new geppettoManager, in principle this is fine since that logic is meant to work with unexpected lost connection that will have a return code different from a closed websocket. However, what we need to do geppetto wise is to check if the geppettoManager we are trying to resume is still existing, if not force the frontend to trigger a reload since the data are not available.