Dear Emanuele,
Thanks for the post and welcome to the ROOT Community!
I am sorry ROOT stopped working for you, probably after moving to macos15 or the newest CLT. You may find this topic informative: ROOT on macOS 15 / Xcode 16 - #8 by Danilo
There is a description of the current status of ROOT and a potential workaround which could unblock you today while you wait for the forthcoming 6.32 release.
Cheers,
Danilo