ci: add workflow for frontend typecheck and build

Author: luoingly

.github/workflows/frontend-test.yml

@@ -0,0 +1,51 @@
+name: Frontend Typecheck and Build
+permissions:
+  contents: read
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+    paths:
+      - "frontend/**"
+      - "shared/**"
+  workflow_dispatch:
+
+jobs:
+  frontend:
+    name: Frontend Typecheck & Build
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: frontend
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Use Node.js 24
+        uses: actions/setup-node@v4
+        with:
+          node-version: 24
+
+      - name: Install pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: 10
+          run_install: false
+
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+
+      - name: Build shared
+        run: pnpm --filter shared build
+
+      - name: Typecheck
+        run: pnpm typecheck
+        env:
+          CI: true
+
+      - name: Build
+        run: pnpm build
+        env:
+          CI: true