Function monitor_log_path 

pub fn monitor_log_path(project_root: &Path, phase: PhaseId) -> PathBuf

Path to the pipe-owning monitor’s own log for a phase (Phase 31).

The monitor is a detached process whose stdio is not the operator’s terminal — anything it prints to its own stdout goes nowhere. Every “log loudly” obligation in this phase (the D-04 idle-timeout clamp, the D-11 opt-out notice) writes here instead, so a loud message is actually readable after the fact.