Function default_sessions_root 

pub fn default_sessions_root() -> Result<PathBuf>

The machine’s DEFAULT sessions root — sessions_root() with the WIRE_HOME override deliberately ignored. This is where the real operator install lives even when the calling process runs under a temp/test WIRE_HOME. Used by wire nuke’s host guard, whose whole point is to see past the caller’s env to what the machine-global teardown would actually hit.