docs(faq): harmonize desktop node environment FAQ across locales

Synchronize content structure and technical details between English and Chinese versions. Align technical accuracy while maintaining locale-specific presentation.

Co-Authored-By: Hagicode <noreply@hagicode.com>
Signed-off-by: newbe36524 <newbe36524@qq.com>

Author: newbe36524

src/content/docs/en/faq/desktop-node-environment.mdx

@@ -36,3 +36,15 @@ HAGICODE_PORTABLE_TOOLCHAIN_ROOT=/path/to/portable-fixed/toolchain
 ```
 
 This variable means the Desktop-managed runtime environment recognized the bundled toolchain root. Seeing this path does not mean Desktop changed your system Node; it only means Desktop is using the Node environment shipped with the app inside its own runtime scope.
+
+## Where Desktop installs managed npm packages
+
+Desktop keeps runtime files and mutable npm package files in different locations. The bundled toolchain path such as `portable-fixed/toolchain/node` is the immutable source for the Desktop-managed `node` and `npm` commands. Managed global packages are installed under the Electron user data directory instead:
+
+```text
+userData/node22/npmGlobal
+```
+
+If Desktop later moves to Node 24, it uses a separate package tree such as `userData/node24/npmGlobal`. Packages installed for Node 22 remain on disk but are not treated as installed for Node 24 until they are reinstalled into the new Node-major prefix.
+
+Desktop dependency status only checks the active `userData/node<major>/npmGlobal` prefix. Package files outside that prefix are ignored by dependency management.

src/content/docs/faq/desktop-node-environment.mdx

@@ -36,3 +36,15 @@ HAGICODE_PORTABLE_TOOLCHAIN_ROOT=/path/to/portable-fixed/toolchain
 ```
 
 这个变量表示当前 Desktop 管理的运行环境已经识别到内置工具链根目录。看到这类路径并不表示 Desktop 修改了你的系统 Node；它只说明 Desktop 在自己的运行范围内使用了随应用提供的 Node 环境。
+
+## Desktop 把托管 npm 包安装到哪里
+
+Desktop 会把运行时文件和可变的 npm 包文件放在不同位置。类似 `portable-fixed/toolchain/node` 的内置工具链路径只作为 Desktop 托管的 `node` 和 `npm` 命令来源，不再作为全局 npm 包安装目录。托管的全局包会安装到 Electron 的用户数据目录：
+
+```text
+userData/node22/npmGlobal
+```
+
+如果 Desktop 后续切换到 Node 24，会使用独立的 `userData/node24/npmGlobal` 包目录。Node 22 下已经安装的包会保留在磁盘上，但不会被 Node 24 视为已安装，需要重新安装到新的主版本目录中。
+
+Desktop 的依赖项状态只检查当前生效的 `userData/node<major>/npmGlobal` 前缀。这个前缀之外的包文件不会参与依赖项管理判断。