Fix bugs reported in Discord

- Fixes ferry flights causing errors when "Nothing" is not available
- Logs a warning when a frontline stance is suddenly no longer available and uses defense stance as fallback which used to be the default. An investigation is still required to determine the cause of this...

game/ground_forces/ai_ground_planner.py

@@ -151,7 +151,12 @@ class GroundPlanner:
             while available > 0:
                 if len(self.connected_enemy_cp) > 0:
                     enemy_cp: ControlPoint = random.choice(self.connected_enemy_cp)
-                    frontline_stance = self.cp.stances[enemy_cp.id]
+                    frontline_stance = self.cp.stances.get(enemy_cp.id)
+                    if not frontline_stance:
+                        logging.warning(
+                            f"{self.cp.name} lost its frontline stance for {enemy_cp.name}"
+                        )
+                        frontline_stance = CombatStance.DEFENSIVE
                     group_size_choice = GROUP_SIZES_BY_COMBAT_STANCE[frontline_stance]
                     if role == CombatGroupRole.SHORAD:
                         count = 1

game/missiongenerator/aircraft/aircraftbehavior.py

@@ -351,6 +351,8 @@ class AircraftBehavior:
         preferred_task: Type[MainTask],
         fallback_task: Optional[Type[MainTask]] = None,
     ) -> None:
+        ac_type = flight.unit_type.dcs_unit_type.id
+
         # Not all aircraft are always compatible with the preferred task,
         # so a common fallback is to use CAS instead.
         # Sometimes it's also the other way around,
@@ -362,8 +364,12 @@ class AircraftBehavior:
             group.task = preferred_task.name
         elif fallback_task and fallback_task in flight.unit_type.dcs_unit_type.tasks:
             group.task = fallback_task.name
+        elif flight.unit_type.dcs_unit_type.task_default and preferred_task == Nothing:
+            group.task = flight.unit_type.dcs_unit_type.task_default.name
+            logging.warning(
+                f"{ac_type} is not capable of 'Nothing', using default task '{group.task}'"
+            )
         else:
-            ac_type = flight.unit_type.dcs_unit_type.id
             fallback_part = f" nor {fallback_task.name}" if fallback_task else ""
             raise RuntimeError(
                 f"{ac_type} is neither capable of {preferred_task.name}"