feat(pair-corpus-honesty): add vibe-py, vfc-js and agent-vfc slices with mechanism vocabulary

Tasks 1.1, 5.1, 5.2, 5.4 and the data half of 5.3.

- mechanisms.toml: closed vocabulary v1 (20 ids) every expected row cites.
- vibe-py: 35 Real-Vuln-Benchmark pairs (Apache-2.0), human provenance only
  because the LLM-generated repositories carry no license (escalated).
- vfc-js: 17 Node fix-commit pairs harvested upstream (MIT/Apache-2.0),
  SecBench.js itself is not vendored (no license); sinks derived on 13/17.
- agent-vfc: 29 agent-trailer fixes as catalog-candidates.toml plus
  REVIEW.md; the loaded catalog stays empty until a human reviews them.
- datasets.toml and README document every slice and its review status.

Co-Authored-By: Claude Fable 5.1 <[email protected]>
Claude-Session: https://claude.ai/code/session_01T7XD7x5KonMdmGRkp63EQG

benchmarks/pairs/vfc-js/dns-sync-0-1-0/fixed.js

@@ -0,0 +1,38 @@
+// Provenance: skoranga/node-dns-sync  (fixed).
+// repo: skoranga/node-dns-sync
+// commit: d9abaae384b198db1095735ad9c1c73d7b890a0d
+// parent: b748fe77a87749d95876028eda8e759109be4c73
+// commit_url: https://github.com/skoranga/node-dns-sync/commit/d9abaae384b198db1095735ad9c1c73d7b890a0d
+// cve: CVE-2014-9682
+// license: MIT
+// function: resolve
+// relpath: lib/dns-sync.js
+// provenance: human
+// mechanism: source_reaches_sink
+// upstream_start: 19
+
+module.exports = {
+    resolve: function resolve(hostname) {
+        var output,
+            nodeBinary = process.execPath;
+
+        if (!isValidHostName(hostname)) {
+            console.error('Invalid hostname:', hostname);
+            return null;
+        }
+
+        var scriptPath = path.join(__dirname, "../scripts/dns-lookup-script"),
+            response,
+            cmd = util.format('"%s" "%s" %s', nodeBinary, scriptPath, hostname);
+
+        response = shell.exec(cmd, {silent: true});
+        if (response && response.code === 0) {
+            output = response.output;
+            if (output && net.isIP(output)) {
+                return output;
+            }
+        }
+        debug('hostname', "fail to resolve hostname " + hostname);
+        return null;
+    }
+};