feat: Migrate web-dashboard CI workflow from npm to pnpm

- Replace npm cache with pnpm setup and store caching in CI workflow
- Add pnpm/action-setup@v4 with version 9
- Configure pnpm store path caching with pnpm-lock.yaml hash key
- Update install command to use pnpm install --frozen-lockfile instead of npm ci
- Update lint and build commands to use pnpm run instead of npm run

.github/workflows/ci.yml

@@ -79,16 +79,33 @@ jobs:
         uses: actions/setup-node@v4
         with:
           node-version: '20'
-          cache: 'npm'
-          cache-dependency-path: apps/web-dashboard/package-lock.json
+
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: 9
+
+      - name: Get pnpm store directory
+        id: pnpm-cache
+        shell: bash
+        run: |
+          echo "STORE_PATH=$(pnpm store path)" >> $GITHUB_OUTPUT
+
+      - name: Setup pnpm cache
+        uses: actions/cache@v4
+        with:
+          path: ${{ steps.pnpm-cache.outputs.STORE_PATH }}
+          key: ${{ runner.os }}-pnpm-store-${{ hashFiles('**/pnpm-lock.yaml') }}
+          restore-keys: |
+            ${{ runner.os }}-pnpm-store-
 
       - name: Install dependencies
         working-directory: apps/web-dashboard
-        run: npm ci
+        run: pnpm install --frozen-lockfile
 
       - name: Run linter
         working-directory: apps/web-dashboard
-        run: npm run lint || true
+        run: pnpm run lint || true
 
       - name: Run type check
         working-directory: apps/web-dashboard
@@ -96,7 +113,7 @@ jobs:
 
       - name: Build
         working-directory: apps/web-dashboard
-        run: npm run build
+        run: pnpm run build
 
   docker-build:
     name: Docker Build