Change ideal monster state in MonsterUse only if monster is idle

dlls/monsters.cpp

@@ -571,6 +571,7 @@ void CBaseMonster::MonsterThink( void )
 //=========================================================
 void CBaseMonster::MonsterUse( CBaseEntity *pActivator, CBaseEntity *pCaller, USE_TYPE useType, float value )
 {
+	if (m_MonsterState == MONSTERSTATE_IDLE)
 		m_IdealMonsterState = MONSTERSTATE_ALERT;
 }