Only visiting heroes can now activate manual rewardable buildings

- This is more clear - in case if building generates queries
- Avoids some edge cases, like what to do if building is single-use and
town has 2 heroes
- In line with hota version of this feature

client/windows/CCastleInterface.cpp

@@ -845,7 +845,18 @@ bool CCastleBuildings::buildingTryActivateCustomUI(BuildingID buildingToTest, Bu
 
 void CCastleBuildings::enterRewardable(BuildingID building)
 {
-	LOCPLINT->cb->visitTownBuilding(town, building);
+	if (town->visitingHero == nullptr)
+	{
+		MetaString message;
+		message.appendTextID("core.genrltxt.273"); // only visiting heroes may visit %s
+		message.replaceTextID(town->town->buildings.at(building)->getNameTextID());
+
+		LOCPLINT->showInfoDialog(message.toString());
+	}
+	else
+	{
+		LOCPLINT->cb->visitTownBuilding(town, building);
+	}
 }
 
 void CCastleBuildings::enterBlacksmith(BuildingID building, ArtifactID artifactID)

docs/modders/Entities_Format/Town_Building_Format.md

@@ -197,6 +197,7 @@ These are just a couple of examples of what can be done in VCMI. See vcmi config
 	"bonuses" : [ BONUS_FORMAT ]
 	
 	// If set to true, this building will not automatically activate on new day or on entering town and needs to be activated manually on click
+	// Note that such building can only be activated by visiting hero, and not by garrisoned hero.
 	"manualHeroVisit" : false,
 	
 	// Bonuses provided by this special building if this building or any of its upgrades are constructed in town

server/CGameHandler.cpp

@@ -2175,7 +2175,7 @@ bool CGameHandler::visitTownBuilding(ObjectInstanceID tid, BuildingID bid)
 
 	if (t->rewardableBuildings.count(bid))
 	{
-		auto & hero = t->garrisonHero ? t->garrisonHero : t->visitingHero;
+		auto & hero = t->visitingHero;
 		auto * building = t->rewardableBuildings.at(bid);
 
 		if (hero && t->town->buildings.at(bid)->manualHeroVisit)