feat(Core/Achievements): Add configurable realm first kill time window (#24920)

src/server/game/World/WorldConfig.cpp

@@ -674,4 +674,7 @@ void WorldConfig::BuildConfigCache()
     SetConfigValue<uint32>(CONFIG_SCOURGEINVASION_COUNTER_THIRD, "ScourgeInvasion.CounterThird", 150);
 
     SetConfigValue<std::string>(CONFIG_NEW_CHAR_STRING, "PlayerStart.String", "");
+
+    // Achievement
+    SetConfigValue<uint32>(CONFIG_ACHIEVEMENT_REALM_FIRST_KILL_WINDOW, "Achievement.RealmFirstKillWindow", 60);
 }

src/server/game/World/WorldConfig.h

@@ -489,6 +489,7 @@ enum ServerConfigs
     RATE_MISS_CHANCE_MULTIPLIER_TARGET_PLAYER,
     CONFIG_NEW_CHAR_STRING,
     CONFIG_VALIDATE_SKILL_LEARNED_BY_SPELLS,
+    CONFIG_ACHIEVEMENT_REALM_FIRST_KILL_WINDOW,
 
     MAX_NUM_SERVER_CONFIGS
 };