It’s been a long time since one country absorbed another after a war.
Well, North Viet Nam certainly absorbed South Viet Nam in 1975. Also, Yugoslavians were absorbed into Croatia, Serbia, Bosnia etc.
The point is, in none of these cases did the UN see fit to “create” a permanent refugee situation as they did with the “Palestinians”, who were actually Jordanians.
The losers were absorbed, or, they moved on...