feat(real-world-vfc-slice): add labeled OpenSSL/Firefox/Chromium/curl pair corpus

Harvest 176 isolated vuln-vs-fix functions (109 CVEs, 352 training rows)
into benchmarks/pairs/vfc with provenance and a JSONL training manifest.
Score the slice as an honesty dashboard (ousast pairs --slice vfc);
keep the pair gate on the local fixtures only.

benchmarks/pairs/vfc/curl-cve-2022-22576-conn_free/fixed.c

@@ -0,0 +1,54 @@
+/* Provenance: curl/curl conn_free (fixed).
+ * repo: curl/curl
+ * commit: 852aa5ad351ea53e5f01d2f44b5b4370c2bf5425
+ * parent: ff2f3e836702daa82e2356195482fcc95f4257dc
+ * commit_url: https://github.com/curl/curl/commit/852aa5ad351ea53e5f01d2f44b5b4370c2bf5425
+ * cve: CVE-2022-22576
+ * license: curl
+ * function: conn_free
+ * relpath: lib/url.c
+ */
+
+static void conn_free(struct connectdata *conn)
+{
+  DEBUGASSERT(conn);
+
+  Curl_free_idnconverted_hostname(&conn->host);
+  Curl_free_idnconverted_hostname(&conn->conn_to_host);
+#ifndef CURL_DISABLE_PROXY
+  Curl_free_idnconverted_hostname(&conn->http_proxy.host);
+  Curl_free_idnconverted_hostname(&conn->socks_proxy.host);
+  Curl_safefree(conn->http_proxy.user);
+  Curl_safefree(conn->socks_proxy.user);
+  Curl_safefree(conn->http_proxy.passwd);
+  Curl_safefree(conn->socks_proxy.passwd);
+  Curl_safefree(conn->http_proxy.host.rawalloc); /* http proxy name buffer */
+  Curl_safefree(conn->socks_proxy.host.rawalloc); /* socks proxy name buffer */
+  Curl_free_primary_ssl_config(&conn->proxy_ssl_config);
+#endif
+  Curl_safefree(conn->user);
+  Curl_safefree(conn->passwd);
+  Curl_safefree(conn->sasl_authzid);
+  Curl_safefree(conn->options);
+  Curl_safefree(conn->oauth_bearer);
+  Curl_dyn_free(&conn->trailer);
+  Curl_safefree(conn->host.rawalloc); /* host name buffer */
+  Curl_safefree(conn->conn_to_host.rawalloc); /* host name buffer */
+  Curl_safefree(conn->hostname_resolve);
+  Curl_safefree(conn->secondaryhostname);
+  Curl_safefree(conn->connect_state);
+
+  conn_reset_all_postponed_data(conn);
+  Curl_llist_destroy(&conn->easyq, NULL);
+  Curl_safefree(conn->localdev);
+  Curl_free_primary_ssl_config(&conn->ssl_config);
+
+#ifdef USE_UNIX_SOCKETS
+  Curl_safefree(conn->unix_domain_socket);
+#endif
+
+#ifdef USE_SSL
+  Curl_safefree(conn->ssl_extra);
+#endif
+  free(conn); /* free all the connection oriented data */
+}