Limit task type combo box to valid mission types.

theater/theatergroundobject.py

@@ -1,11 +1,9 @@
-from typing import List
 import uuid
 
 from dcs.mapping import Point
 
 from .missiontarget import MissionTarget
 
-
 NAME_BY_CATEGORY = {
     "power": "Power plant",
     "ammo": "Ammo depot",
@@ -102,3 +100,11 @@ class TheaterGroundObject(MissionTarget):
     @property
     def name(self) -> str:
         return self.obj_name
+
+    def parent_control_point(
+            self, theater: "ConflictTheater") -> "ControlPoint":
+        """Searches the theater for the parent control point."""
+        for cp in theater.controlpoints:
+            if cp.id == self.cp_id:
+                return cp
+        raise RuntimeError("Could not find matching control point in theater")