Function has_project_marker 

pub fn has_project_marker(dir: &Path) -> bool

Returns true if dir contains at least one known project marker.

TCC guard (#356): a launchd-owned process (daemon/proxy/auto-updater) must not stat marker files under ~/Documents & co. — the probe itself pops the macOS privacy prompt. For those processes this conservatively reports “no marker” without touching the filesystem.