That woman standing in front of you in the queue at Costa? She could be a spy. The fella scrolling on his phone as he waits at the tram stop? He might have spent his day eavesdropping on a terrorist network. Since late 2019 Manchester city centre has been home to signals intelligence agency GCHQ. Inside Heron House, opposite the town hall, hundreds of spooks work round the clock on missions such as defending the UK against potential cyber-attacks from China and Russia and the digital surveillance of terrorists and organised crime. Read more: Inside Manchester's top secret spy headquarters…