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

@@ -105,8 +105,8 @@
       "repo": "https://github.com/nextlevelbuilder/ui-ux-pro-max-skill.git",
       "ref": "main",
       "adapter": "claude-skill",
-      "commit": "d14efff8ed1faa4187f004f79926f428c8074ec7",
-      "syncedAt": "2026-10-23T16:00:00Z"
+      "commit": "28b3b8dee8c976df4fa3e94aed4e092ad43fcb03",
+      "syncedAt": "2026-10-26T16:00:00Z"
     },
     {
       "id": "caveman",
@@ -132,8 +132,8 @@
       "repo": "https://github.com/shadcn-ui/ui.git",
       "ref": "main",
       "adapter": "claude-skill",
-      "commit": "481d523374745e77d0cf9c53a4115ab5dd7c8481",
-      "syncedAt": "2026-10-25T16:00:00Z"
+      "commit": "8f04138777c1b6996e709993362a7b0a12888ecf",
+      "syncedAt": "2026-10-26T16:00:00Z"
     },
     {
       "id": "frontend-slides",
@@ -258,8 +258,8 @@
       "repo": "https://github.com/vercel/next.js.git",
       "ref": "canary",
       "adapter": "skill-collection",
-      "commit": "cbf49db30a655ac17c92c2951885c4256db14b9e",
-      "syncedAt": "2026-10-25T16:00:00Z"
+      "commit": "b0e1bf792f18c039933d8a9ce9d50d35f930f1be",
+      "syncedAt": "2026-10-26T16:00:00Z"
     },
     {
       "id": "shuorenhua",