Where are my AudioUnit/Carbon folders?

I’ve got a fairly fresh install of Catalina running Xcode 11.6 and I’m looking for some of the files that are used when managing AU resources. When looking for this folder, I find I don’t have an Extras folder!

ls /Applications/Xcode.app/Contents/Developer/
Applications	Library		Makefiles	Platforms	Toolchains	Tools		usr

I’m also missing the final subdirectory Headers here

ls /System/Library/Frameworks/CoreServices.framework/Frameworks/CarbonCore.framework/Versions/A
CarbonCore	Resources	Support		_CodeSignature

Is this expected? Where did these files go?

This path is also included by the xcode project when building AUs. I’m guessing what happens is that JUCE uses include paths for where things used to be and where things ended up when Apple moved them so that things work better across different OS versions.