Add GitHub Actions workflow to deploy on push to main

Builds the Astro site and runs `wrangler deploy` on every push to main,
replacing the disconnected Cloudflare Git integration. Failures surface
in the Actions tab. Requires repo secrets CLOUDFLARE_API_TOKEN and
CLOUDFLARE_ACCOUNT_ID.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: duremovich

.github/workflows/deploy.yml

@@ -0,0 +1,32 @@
+name: Deploy
+
+on:
+  push:
+    branches: [main]
+  workflow_dispatch:
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Node
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Build
+        run: npm run build
+
+      - name: Deploy to Cloudflare
+        uses: cloudflare/wrangler-action@v3
+        with:
+          apiToken: ${{ secrets.CLOUDFLARE_API_TOKEN }}
+          accountId: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
+          command: deploy