chore: update Node.js version to 21 and add npm cache for frontend dependencies

Author: peterbitfly

.github/workflows/frontend-lint-format.yml

@@ -25,9 +25,11 @@ jobs:
     - name: Checkout Repository
       uses: actions/checkout@v3
     - name: Setup Node Environment
-      uses: actions/setup-node@v3
+      uses: actions/setup-node@v4
       with:
-        node-version: 18
+        node-version: 21
+        cache: 'npm'
+        cache-dependency-path: frontend/package-lock.json
     - name: Install Dependencies
       working-directory: frontend
       env: