chore: Remove nginx - use direct Caddy routing

- Remove nginx service from docker-compose
- Services bind to localhost:3000/3001 only
- Add Caddy configuration guide
- Update README with simplified structure
- External reverse proxy handles SSL/routing

docs/CADDY-CONFIG.md

@@ -0,0 +1,50 @@
+# Caddy Configuration
+
+Caddy handles SSL termination and routes to the application services.
+
+## Caddyfile Example
+
+```caddy
+coop.hobokenchicken.com {
+    # Frontend (Next.js)
+    handle_path /* {
+        reverse_proxy localhost:3000
+    }
+
+    # API routes
+    handle_path /api/* {
+        reverse_proxy localhost:3001
+    }
+
+    # Webhooks
+    handle_path /webhooks/* {
+        reverse_proxy localhost:3001
+    }
+
+    # WebSocket support
+    handle_path /socket.io/* {
+        reverse_proxy localhost:3001
+    }
+}
+```
+
+## Docker Compose (no nginx)
+
+Services bind to localhost only (`127.0.0.1`):
+
+- **Frontend**: `127.0.0.1:3000` 
+- **Backend**: `127.0.0.1:3001`
+- **Postgres**: `5432` (internal only)
+- **Redis**: `6379` (internal only)
+
+## Start Stack
+
+```bash
+# Start services
+docker-compose up -d
+
+# Verify
+curl http://localhost:3001/health
+```
+
+Caddy automatically provisions SSL and routes traffic.