simplify unused objectives display and tie-break

src/warchron/model/campaign.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 from uuid import uuid4
-from typing import Any, Dict, List
+from typing import Any, Dict, List, Set
 
 from warchron.model.exception import ForbiddenOperation, RequiresConfirmation
 from warchron.model.campaign_participant import CampaignParticipant
@@ -146,6 +146,15 @@ class Campaign:
             for sect in self.sectors.values()
         )
 
+    def get_objectives_used_as_maj_or_min(self) -> List[str]:
+        obj_ids: Set[str] = set()
+        for sector in self.sectors.values():
+            if sector.major_objective_id:
+                obj_ids.add(sector.major_objective_id)
+            if sector.minor_objective_id:
+                obj_ids.add(sector.minor_objective_id)
+        return [obj_id for obj_id in obj_ids]
+
     def add_sector(
         self,
         name: str,

src/warchron/model/war.py

@@ -175,6 +175,14 @@ class War:
     def get_all_objectives(self) -> List[Objective]:
         return list(self.objectives.values())
 
+    def get_objectives_used_as_maj_or_min(self) -> List[Objective]:
+        obj_ids: set[str] = set()
+        for camp in self.campaigns:
+            obj_ids.update(camp.get_objectives_used_as_maj_or_min())
+        return [
+            self.objectives[obj_id] for obj_id in obj_ids if obj_id in self.objectives
+        ]
+
     def get_objective_name(self, objective_id: str | None) -> str:
         if objective_id is None:
             return ""