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.

README.md

@@ -23,6 +23,8 @@ Codex 插件页的大标题按 marketplace 来源分组，不是按插件 `categ
 
 有些插件是 skill 集合，安装一个 `plugin-id` 后会同时提供多个 `$skill-name`。可安装项和安装后可用的 skills 均以 Codex 的实际输出为准。
 
+例如 `grill-me` 插件会同时安装用户入口 `$grill-me` 和必需的基础能力 `$grilling`；请安装插件整体，不要只复制其中一个 skill 目录。
+
 如果插件刚安装到当前 Codex 会话中，启动新的 Codex thread 或新的 Codex 调用后再依赖新增 skills/hooks/MCP/app 配置。
 
 卸载插件：