docs: Add VS Code workspace requirement for LaTeX Workshop configuration (#64)

* Initial plan

* Add VS Code workspace requirement documentation to README files

Co-authored-by: RizhongLin <59563695+RizhongLin@users.noreply.github.com>

* Refine VS Code docs: integrate workspace requirement more concisely

Co-authored-by: RizhongLin <59563695+RizhongLin@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: RizhongLin <59563695+RizhongLin@users.noreply.github.com>

Author: Copilot

README-EN.md

@@ -143,7 +143,7 @@ make wordcount          # word count
 
 ###### Configuring VS Code
 
-Install the LaTeX Workshop plugin in VS Code, and then open the root directory of this project.
+Install the LaTeX Workshop plugin in VS Code, and then **open the root directory of this project directly** (i.e., the `tongji-undergrad-thesis` folder, not a parent folder, otherwise `.vscode/settings.json` will not take effect).
 
 ###### Compile Project Using Workshop Features
 

README.md

@@ -142,7 +142,7 @@ make wordcount          # wordcount
 
 ###### 配置 VS Code
 
-在 VS Code 中安装 LaTeX Workshop 插件，然后打开本项目根目录。
+在 VS Code 中安装 LaTeX Workshop 插件，然后**直接打开本项目根目录**（即 `tongji-undergrad-thesis` 文件夹，而非其上层文件夹，否则 `.vscode/settings.json` 配置无法生效）。
 
 ###### 通过 Workshop 提供的功能编译项目