Replace CP integer ID with a UUID.

This allows unique identification across saves. The front-end needs to
be able to differentiate the first carrier in game A and the first
carrier in game B, but because carriers (and other non-airfield CPs) are
assigned IDs sequentially, collisions were to be expected. The front-end
can't tell the difference between a reloaded game and a new turn, so we
need to ensure different IDs across games.

This is a handy cleanup anyway, since callers constructing CPs no longer
need to manually track the CP ID counter.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/2078.

game/server/eventstream/models.py

@@ -32,7 +32,7 @@ class GameUpdateEventsJs(BaseModel):
     updated_front_lines: set[UUID]
     deleted_front_lines: set[UUID]
     updated_tgos: set[UUID]
-    updated_control_points: set[int]
+    updated_control_points: set[UUID]
     reset_on_map_center: LeafletPoint | None
     game_unloaded: bool
     new_turn: bool