feat: add service catalog management with policy integration for domain-based resource access control

Add ServiceCatalogItem type and services CRUD API endpoints (list, create, update, delete). Extend Policy type to include services array with domain, upstream_ip, proxy_ip, and ports metadata.

Add ServicesPage component with table view and create/edit modals for managing service definitions. Include service name, domain, proxy, and upstream columns with port parsing logic.

Integrate service selection

admin-web/src/components/Layout.tsx

@@ -5,6 +5,7 @@ const items = [
   ["Users", "/users"],
   ["Groups", "/groups"],
   ["Devices", "/devices"],
+  ["Services", "/services"],
   ["Policies", "/policies"],
   ["Gateways", "/gateways"],
   ["Audit", "/audit"],