add a build workflow

Author: joshsny

.github/workflows/build.yml

@@ -0,0 +1,31 @@
+name: Build
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v5
+        with:
+          persist-credentials: false
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: 'pnpm'
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+      - name: Build agent package
+        run: pnpm --filter agent build
+      - name: Build array app
+        run: pnpm --filter array package