Sync third-party and MCP marketplace plugins

Constraint: Public skills are published only by explicit administrator action unless they are tracked third-party market sources.
Confidence: high
Scope-risk: narrow
Directive: Keep private/internal skills out of the public marketplace and preserve normal incremental market Git history.
Tested: Marketplace validation passed.

plugins/codex/plugins/next-skills/THIRD_PARTY_SOURCE.json

@@ -2,8 +2,8 @@
   "sourceId": "next-skills",
   "repo": "https://github.com/vercel/next.js.git",
   "ref": "canary",
-  "commit": "41b823880d688b3e9f9aae3323b08ddd457240c2",
+  "commit": "d3e41fb496aeddeb448ba454bd663c36ea8183a5",
   "adapter": "skill-collection",
   "sourcePath": "skills",
-  "syncedAt": "2026-07-13T16:00:00Z"
+  "syncedAt": "2026-07-20T16:00:00Z"
 }