Publish shadcn as a third-party market source

Add shadcn-ui/ui skills/shadcn to the external source registry and generate the public Codex plugin with localized Chinese marketplace metadata. Index the plugin in both marketplace entry points and lock the synced upstream commit.

Constraint: Third-party plugin contents are generated from config/external-sources.json and locked to the upstream commit recorded in external-sources.lock.json.
Rejected: Hand-editing generated shadcn plugin metadata | Localized display fields belong in manifestOverrides and skillDescriptions so future syncs preserve them.
Confidence: high
Scope-risk: narrow
Directive: Re-run the external source sync instead of manually editing plugins/codex/plugins/shadcn when upstream changes.
Tested: python scripts/validate_marketplace.py; python /Users/eapil/.codex/skills/.system/plugin-creator/scripts/validate_plugin.py plugins/codex/plugins/shadcn; git diff --check.
Not-tested: Codex marketplace install/remove smoke test was not run.

config/external-sources.json

@@ -86,6 +86,58 @@
         "README.md",
         "LICENSE"
       ]
+    },
+    {
+      "id": "shadcn",
+      "repo": "https://github.com/shadcn-ui/ui.git",
+      "ref": "main",
+      "adapter": "claude-skill",
+      "pluginName": "shadcn",
+      "category": "开发工具",
+      "skillPath": "skills/shadcn",
+      "brandColor": "#09090B",
+      "manifestOverrides": {
+        "version": "0.1.0",
+        "description": "面向 shadcn/ui 项目的组件安装、组件查询、文档检索、预设处理和实现规范工作流。",
+        "author": {
+          "name": "shadcn",
+          "url": "https://github.com/shadcn-ui"
+        },
+        "homepage": "https://ui.shadcn.com",
+        "repository": "https://github.com/shadcn-ui/ui",
+        "license": "MIT",
+        "keywords": [
+          "shadcn",
+          "shadcn-ui",
+          "components",
+          "design-system",
+          "react",
+          "tailwind"
+        ],
+        "interface": {
+          "displayName": "shadcn/ui",
+          "shortDescription": "shadcn/ui 项目、组件、注册表和预设的开发工作流。",
+          "longDescription": "shadcn/ui skill 提供项目上下文读取、组件搜索、组件文档检索、CLI 操作约束、注册表组件接入、预设处理以及常见组件实现规范，适合在 React、Next.js、Tailwind 和 shadcn/ui 项目中使用。",
+          "developerName": "shadcn",
+          "category": "开发工具",
+          "defaultPrompt": [
+            "使用 shadcn/ui 帮我添加或修复组件。",
+            "使用 shadcn/ui 帮我检查这个项目的组件实现规范。"
+          ],
+          "websiteURL": "https://ui.shadcn.com",
+          "privacyPolicyURL": "https://github.com/shadcn-ui/ui",
+          "termsOfServiceURL": "https://github.com/shadcn-ui/ui",
+          "brandColor": "#09090B",
+          "composerIcon": "./skills/shadcn/assets/shadcn-small.png",
+          "logo": "./skills/shadcn/assets/shadcn.png"
+        }
+      },
+      "skillDescriptions": {
+        "shadcn": "用于 shadcn/ui 项目初始化、组件安装、组件文档检索、注册表组件接入、预设处理和实现规范检查的开发工作流。"
+      },
+      "includeRootFiles": [
+        "LICENSE.md"
+      ]
     }
   ]
 }