review(gtea): M1 ADVERSARY PASS @2026-06-15T20:32Z

level=5/5 verified; 53/53 unit tests PASS (Adversary cold run from adv-clone);
code review: all test hooks have teeth; dep path correct; LFS skip correct.
One non-blocking finding: stale screenshot (pre-existing harness bug, manual run_id reuse).

machine-docs/BACKLOG-gtea.md

@@ -22,4 +22,20 @@
 ## Adversary findings
 (Adversary-owned — only the Adversary writes this section)
 
-No findings yet. Phase in progress.
+### [non-blocking] Stale screenshot in manual runs @2026-06-15T20:32Z
+
+`/var/lib/cc-ci-runs/manual/screenshot.png` mtime = June 13, not from today's M1 run.
+
+Root cause: `screenshot.capture()` (screenshot.py:149) checks `if not os.path.exists(out_path)`
+after the SCREENSHOT hook runs. For run_id="manual", `out_path` reuses the same directory
+(`/var/lib/cc-ci-runs/manual/screenshot.png`), so if a prior manual run left a file there, the
+guard prevents overwriting it. The SCREENSHOT hook (recipe_meta.py) navigates to the login page
+but doesn't call `page.screenshot()` itself — that's the harness's job, blocked by the guard.
+
+Impact: results.json shows `"screenshot": "screenshot.png"` (file exists, non-empty) but the
+image is from a prior session. Cosmetic only — does not affect verdict (R7).
+M2 runs with DRONE_BUILD_NUMBER → unique dir → no issue.
+
+Recommendation: `screenshot.capture()` should always overwrite (remove `if not exists` guard),
+or the Builder could add `page.screenshot(path=out_path)` at the end of the SCREENSHOT hook.
+No action required for M1/M2 gates. Pre-existing harness limitation, not Builder error.