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.

config/external-sources.lock.json

@@ -87,8 +87,8 @@
       "repo": "https://github.com/hugohe3/ppt-master.git",
       "ref": "main",
       "adapter": "claude-skill",
-      "commit": "3f3f2418163ccb438d010f3acbce4a3651b758a5",
-      "syncedAt": "2026-07-10T16:00:00Z"
+      "commit": "dbf1e363abb4dba36f7c883ee7ba1495073394d0",
+      "syncedAt": "2026-07-11T15:59:59Z"
     },
     {
       "id": "next-skills",
@@ -96,8 +96,8 @@
       "repo": "https://github.com/vercel/next.js.git",
       "ref": "canary",
       "adapter": "skill-collection",
-      "commit": "46681d90f0fd92bb22fbf38b43b507faad47a812",
-      "syncedAt": "2026-07-10T16:00:00Z"
+      "commit": "1bd2fd585aac793ca2589e6f18f17a412fd11005",
+      "syncedAt": "2026-07-11T15:59:59Z"
     }
   ]
 }