ci: Update CircleCI config to use yarn consistently

- Replace npm install with yarn install at root level
- Add descriptive comments in Chinese for build steps
- Streamline dependency installation process in gui directory

The commit message reflects the changes to the CircleCI configuration file, where the main changes involve standardizing the use of yarn for package management and adding clarity through comments. Since no specific issue number was provided in the input, I've excluded the "Closes #" reference.

.circleci/config.yml

@@ -10,13 +10,15 @@ jobs:
       - checkout
       - run: git submodule sync
       - run: git submodule update --init --recursive
-      - run: npm install
+      # 首先在根目录安装依赖
+      - run: yarn install
+      # 然后进入 gui 目录安装依赖并构建
       - run: |
           cd gui
-          yarn
+          yarn install
           yarn vscode
           cd ..
-      - run: npm run build
+      # 最后执行打包
       - run: yarn package
       - persist_to_workspace:
           root: .