ci: install frontend dependencies for collector contract

Author: Curry

.github/workflows/ci.yml

@@ -144,6 +144,21 @@ jobs:
         with:
           python-version-file: ".python-version"
 
+      - name: Setup pnpm for frontend contract checks
+        uses: pnpm/action-setup@v4
+        with:
+          version: 10
+
+      - name: Setup Node for frontend contract checks
+        uses: actions/setup-node@v6
+        with:
+          node-version-file: frontend/.nvmrc
+          cache: pnpm
+          cache-dependency-path: frontend/pnpm-lock.yaml
+
+      - name: Install frontend dependencies for contract checks
+        working-directory: frontend
+        run: pnpm install --frozen-lockfile
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip