fix(plugins): harden imported extension dependencies

README.md

@@ -231,7 +231,7 @@ The control endpoint supports project, session, and Agent workflows plus a revie
 
 Extensions written for the [pi](https://github.com/badlogic/pi-mono) CLI can run inside PI-Desktop's agent unchanged.
 
-A plugin can list them under `contributes.agentExtensions`, or **Plugins → Import pi extension** can wrap an existing extension file or directory in a plugin. If the directory declares npm `dependencies`, they are installed into the generated plugin before its first load (`--ignore-scripts`, so no third-party install script ever runs).
+A plugin can list them under `contributes.agentExtensions`, or **Plugins → Import pi extension** can wrap an existing extension file or directory in a plugin. If the directory declares production or optional npm dependencies, a system `npm` on `PATH` performs a bounded registry-only install before first load (`--ignore-scripts`, so no third-party install script ever runs); release builds do not include standalone Node/npm.
 
 They can register tools, slash commands, and hooks on every turn, tool call, and provider request. They run with the same access as the agent's own tools, gated by the `agent.extension` permission.
 

README.zh-CN.md

@@ -291,7 +291,7 @@ PI_DESKTOP_MCP_CONTROL=1
 
 **Plugins → Import pi extension**
 
-直接把现有 extension 文件或目录包装成 PI-Desktop 插件。若目录声明了 npm `dependencies`，会在首次加载前安装到生成的插件中（`--ignore-scripts`，绝不运行第三方安装脚本）。
+直接把现有 extension 文件或目录包装成 PI-Desktop 插件。若目录声明了生产或可选 npm `dependencies`，`PATH` 中的系统 `npm` 会在首次加载前执行有界的 registry-only 安装（`--ignore-scripts`，绝不运行第三方安装脚本）；发布版不包含独立 Node/npm。
 
 这些扩展可以注册：