ci: add build check for PRs

.github/workflows/build-admin-on-pr.yml

@@ -0,0 +1,25 @@
+name: Build Admin
+
+on: pull_request
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v6
+        with:
+          node-version: '24'
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+        working-directory: ./admin
+
+      - name: Run build
+        run: npm run build
+        working-directory: ./admin