[Swan] default config that works with recent android/win10/win11/macos/ios

[Marc]

> 
> In particular, Win10 still defaults to DH group 2 (1024 bit), which is
> known to be insecure, and libreswan rejects it by default, IIRC.
> I'm not sure about Win11, but I would expect MS to stick to their design.
> 

Yes Indeed. I have made some powershell/regedit scripts that change these defaults. So I can send someone these. Inspecting such files and asking someone to double click them is not ideal, but still doable.