fix: pnpm으로 변경

Author: eeeyooon

.github/workflows/deploy.yml

@@ -17,16 +17,23 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Setup Node
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: 9
+
+      - name: Setup Node.js
         uses: actions/setup-node@v4
         with:
           node-version: 20
+          cache: "pnpm"
 
       - name: Install dependencies
-        run: npm ci
+        run: pnpm install --frozen-lockfile
 
-      - name: Build
-        run: npm run docs:build
+      - name: Build VitePress site
+        run: pnpm run docs:build
+        working-directory: docs
 
       - name: Setup Pages
         uses: actions/configure-pages@v5