Re-audit round 4: 5 blind reviewers over the new surface — 24 fixes, +28 tests

The findings clustered exactly where prediction said: the unreviewed web
layer. The big ones: decisions made while an extract/resolve job runs
are now refused with a 409 (the job's end-of-run rewrite from a
start-of-run snapshot would silently revert them); a cross-origin guard
blocks preflight-free mutations from hostile webpages (bodyless run
triggers, cross-site photo form posts); the JobRunner sets terminal
status in a finally catching BaseException (a greenlet death could
wedge every future run behind 409s) and writes tracebacks into the
visible job log; and a boot token lets clients accept the revision
reset after a server restart instead of freezing forever.

Even the thrice-audited core yielded one HIGH: an unvetoed bare
typo-read sibling of a confident row duplicated its add when the game
wasn't in the collection — diff now treats it as satisfied. Second-copy
adds carry a flag through to_add.csv and the upload log so verify
honestly reports them unverifiable instead of OK. Also: merged_into
chains collapse transitively; diff/enrich treat a BGG queue timeout
like a missing token; enrich prunes orphaned games.json keys; the
wizard shell-quotes .env values and creates the file 0600 from the
first byte; fsio stats the tmp inode before replace and uses unique tmp
names; an explicit missing --config errors; storage state is
owner-only; extract re-extracts corrupt caches, aborts on 3 identical
failures, and exits nonzero when nothing succeeded; torn JSON artifacts
degrade with in-browser warnings instead of 500ing every page; photo
uploads are atomic with cache-invalidation ordered first; the pipeline
page computes `running` before the buttons that depend on it; the
photo dropzone alerts on network failure; and lost-contact banners
clear on recovery everywhere.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tests/test_resolve.py

@@ -660,3 +660,15 @@ def test_reordered_titles_json_cannot_mispair_editions(client, tmp_path):
     assert by_photos["b.jpg"]["match_status"] == "auto"  # kept its resolution
     assert "a.jpg" in by_photos  # newcomer resolved as its own row
     assert len(rows) == 2
+
+
+def test_merged_into_chains_resolve_to_terminal_survivor():
+    # X merged into Y in a prior run; this run merges Y into W — X must
+    # point at W, or diff's one-level photo hop loses X's provenance
+    x = _mrow("Wingspam", "266192", "x.jpg", status="merged")
+    x["merged_into"] = "Wingspan Typo"
+    y = _mrow("Wingspan Typo", "266192", "y.jpg", name="Wingspan")
+    w = _mrow("Wingspan", "266192", "w.jpg", name="Wingspan")
+    dedupe_matches([x, y, w], [])
+    assert y["match_status"] == "merged" and y["merged_into"] == "Wingspan"
+    assert x["merged_into"] == "Wingspan"  # chain collapsed