No Proxy for Xcode 15:
_with Xcode 14 You can modify this file : /Applications/Xcode.app/Contents/SharedFrameworks/ContentDeliveryServices.framework/Versions/A/itms/java/conf/net.properties
and set the following property to true ( false by default ) java.net.useSystemProxies=true_
With Xcode 15, I don't found any solution
**Utilisation of environment variables http_proxy and https_proxy it's useless because it's ignored
#** how I can define a proxy in order to sign with Xcode command lines ?