Fix duplicate conquered villain messages when killing fighters after a duel

Author: miki151

collective.cpp

@@ -747,7 +747,7 @@ const optional<Collective::AlarmInfo>& Collective::getAlarmInfo() const {
 }
 
 bool Collective::needsToBeKilledToConquer(const Creature* c) const {
-  return hasTrait(c, MinionTrait::FIGHTER) || hasTrait(c, MinionTrait::LEADER);
+  return (hasTrait(c, MinionTrait::FIGHTER) && !c->wasDuel()) || hasTrait(c, MinionTrait::LEADER);
 }
 
 bool Collective::creatureConsideredPlayer(Creature* c) const {

creature.cpp

@@ -1703,6 +1703,10 @@ void Creature::removePrivateEnemy(const Creature* c) {
   privateEnemies.erase(c);
 }
 
+bool Creature::wasDuel() const {
+  return !!duelInfo;
+}
+
 void Creature::setDuel(TribeId enemyTribe, Creature* opponent, GlobalTime timeout) {
   duelInfo = DuelInfo{enemyTribe, opponent ? opponent->getUniqueId() : Creature::Id{}, timeout};
   if (steed)

creature.h

@@ -343,6 +343,7 @@ class Creature : public Renderable, public UniqueEntity<Creature>, public OwnedO
   bool canBeCaptured() const;
   void removePrivateEnemy(const Creature*);
   void setDuel(TribeId enemyTribe, Creature* opponent, GlobalTime timeout);
+  bool wasDuel() const;
   const vector<AutomatonPart>& getAutomatonParts() const;
   bool isAutomaton() const;
   void addAutomatonPart(AutomatonPart);