By Jeremy Armstrong Paris is set for the biggest security operation in Olympic history when the Games return to the city for the first time in a century. The “lone wolf” terrorist has been identified as the main danger to an opening ceremony which will see 160 boats take to the River Seine carrying almost 10,000 athletes and officials. At least 45,000 security personnel will be in place on the streets, rooftops and inside buildings. A fleet of tourist vessels and restaurant boats will wend its way along the 6km (3.5m) route from the Austerlitz Bridge, close to Notre Dame, to the banks by the E…