fix: add pnpm as package manager

Author: hieuddo

.github/workflows/nextjs.yml

@@ -39,6 +39,11 @@ jobs:
             echo "command=install" >> $GITHUB_OUTPUT
             echo "runner=yarn" >> $GITHUB_OUTPUT
             exit 0
+          elif [ -f "${{ github.workspace }}/pnpm-lock.yaml" ]; then
+            echo "manager=pnpm" >> $GITHUB_OUTPUT
+            echo "command=install --frozen-lockfile" >> $GITHUB_OUTPUT
+            echo "runner=pnpm" >> $GITHUB_OUTPUT
+            exit 0
           elif [ -f "${{ github.workspace }}/package.json" ]; then
             echo "manager=npm" >> $GITHUB_OUTPUT
             echo "command=ci" >> $GITHUB_OUTPUT
@@ -48,6 +53,11 @@ jobs:
             echo "Unable to determine package manager"
             exit 1
           fi
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+        if: steps.detect-package-manager.outputs.manager == 'pnpm'
+        with:
+          version: 9
       - name: Setup Node
         uses: actions/setup-node@v4
         with: