Add deployment pipeline with Fly.io setup

- Introduced `.woodpecker.yml` for CI/CD pipeline configuration targeting `main` branch.
- Added `fly.toml` for Fly.io deployment settings, including region and deployment checks.
- Created a `Dockerfile` for serving static files via NGINX with SPA routing setup.

.woodpecker.yml

@@ -0,0 +1,11 @@
+pipeline:
+  deploy:
+    image: node:20
+    commands:
+      - curl -L https://fly.io/install.sh | sh
+      - export PATH="$HOME/.fly/bin:$PATH"
+      - flyctl deploy --config fly.toml --app gallus-pub
+    when:
+      event: push
+      branch:
+        - main