Temporary but hands-free JTAG/SWD connection
Is your design price constrained? 
For SWD we need only two wires and a ground connection, so this could be possible solution. This doens't need any soldering. 

https://www.mill-max.com/products/new/zero-profile-bottom-entry-receptacle

For production version, this can be dropped totally. 



Second suggestion

Zero soldering and zero investment for production. I am sure I have also seen fine pitch edge connectors too.