status(cfold): record ghost follow-up audit

machine-docs/STATUS-cfold.md

@@ -58,6 +58,8 @@ Adversary verdict:
 Current work item:
 - full real-CI `!testme` sweep evidence is mostly assembled; one recipe (`ghost`) remains non-green for
   a cfold-neutral upgrade regression on the recipe/environment side
+- fresh artifact audit confirms historical build `185` passed on the same Ghost ref now failing in
+  probe build `559`, so no cfold-local code fix has been identified in this repo yet
 
 ### M2 baseline matrix (built from live PR heads + fresh post-cfold evidence)
 
@@ -93,6 +95,9 @@ Current work item:
 - To isolate cfold from recipe-head drift, a separate probe PR #5 was opened at Ghost's last known-green
   PR head `d42d0f7c` (historical build `185` = L4/L5-equivalent on 2026-06-05). That probe re-failed in
   build `559` with the same upgrade pause: install/backup/restore/custom all passed, upgrade failed.
+- Focused artifact audit after build `559` confirmed the same-ref comparison explicitly:
+  historical build `185` (`d42d0f7c7cf9`) had `upgrade=pass`, while fresh build `559` on that same ref
+  has `upgrade=fail` with the canonical `custom` stage still green.
 - Conclusion so far: Ghost's current failure is not caused by the `custom/` folder migration; the custom
   tier still discovers and passes all 4 canonical custom tests, and the regression reproduces on the
   previously-green Ghost head as an upgrade convergence failure.