unseen: sourcing robustness -- retry transient HTTP/connection errors, shrink the advisory journal

A live G0 sourcing run failed on both: a transient connection/decode error aborted
the whole enumeration (the bare except raised http_failure on the first blip), and
the advisory journal stored full raw advisory JSON and reached 1.77 GB on a near-full
host. Fix: the JSON transport now retries URLError/timeout/ConnectionError/IncompleteRead/
JSONDecodeError through the same attempt-4 backoff as HTTP 5xx/429 (fatal only after the
cap or on a genuinely non-retryable error); enumerate_advisories journals only the fields
resolution/extraction consume via source.reduce_advisory (ghsa id, published/withdrawn,
type, CWE ids, package ecosystem/name for OSV, fix-commit links), with journal_version
bumped to 2 so an old full-format journal is rejected and resume-skip stays intact.

Offline: test_unseen_source/draft/extract 133 passed; ruff + format clean; mypy unchanged
(pre-existing verify.py lambda only).

Co-Authored-By: Claude Opus 4.8 <[email protected]>

benchmarks/unseen/draft.py

@@ -219,7 +219,7 @@ def inputs(used, seed, known_empty, clones):
         "used_set_digest": digest({label: sorted(names) for label, names in used.sources.items()}),
         "known_empty": sorted(known_empty),
         "clone_limit_bytes": getattr(clones, "limit_bytes", 500 * 1024 * 1024),
-        "journal_version": 1,
+        "journal_version": 2,
     }
     # Hardcoded design thresholds and algorithms are covered as well as taxonomy data.
     for name in ("draft", "source", "extract", "eligibility", "journal"):
@@ -235,7 +235,7 @@ def enumerate_advisories(github, journal):
         if key not in journal.rows["advisories"]:
             journal.boundary()
             result = github.advisory_page(page)
-            journal.put("advisories", key, result)
+            journal.put("advisories", key, {"rows": [source.reduce_advisory(row) for row in result["rows"]], "done": result["done"]})
         result = journal.rows["advisories"][key]
         records.update((row["ghsa_id"], row) for row in result["rows"])
         if result["done"]: