With major Persian Gulf aviation hubs largely paralysed by airspace closures amid the escalating conflict involving the US, Israel and Iran, travellers have flocked to direct Asia-Europe routes, driving a sharp surge in airfares.This week, economy class on most direct one-way Beijing-Paris flights is fully booked, with a small number of economy seats – plus premium economy and business class seats – remaining.Economy seats on an Air China flight on Sunday are already booked out, with a one-way...