[IMP] point_of_sale,pos_*: combine ticket and management screens

We are referring to TicketScreen and OrderManagementScreen.
The two screens almost serves the same purpose. There is not much reason
to keep them separate. We combine the two in this commit. Basically,
we remove OrderManagementScreen and its components. Some are kept and
moved to the TicketScreen.

Task-id: 2481404
Part-of: odoo/odoo#75322