ci: add pull request validation workflow

.github/workflows/ci.yml

@@ -0,0 +1,34 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches: [develop, main]
+
+permissions:
+  contents: read
+
+jobs:
+  validate:
+    name: Validate
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Install Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '24.x'
+          cache: npm
+      - name: Install
+        run: npm ci
+      - name: Build
+        run: npm run build
+      - name: Typecheck
+        run: npm run type
+      - name: Test
+        run: npm test
+      - name: Pack
+        run: npm pack --dry-run