feat(sidebar): move Routing/Outbounds to top-level items with clean URLs

- Move Routing out of the Xray Configs submenu; add Routing and Outbounds
  as top-level sidebar items below Hosts
- Give them their own clean routes (/routing, /outbound) instead of
  /xray#routing and /xray#outbound, registered in the React router and the
  Go SPA shell so direct links and refresh work
- XrayPage derives the active section from the pathname for those routes
- Add menu.routing and menu.outbounds translation keys across all locales

frontend/src/routes.tsx

@@ -30,6 +30,8 @@ const routes: RouteObject[] = [
       { path: 'hosts', element: withSuspense(<HostsPage />) },
       { path: 'settings', element: withSuspense(<SettingsPage />) },
       { path: 'xray', element: withSuspense(<XrayPage />) },
+      { path: 'outbound', element: withSuspense(<XrayPage />) },
+      { path: 'routing', element: withSuspense(<XrayPage />) },
       { path: 'api-docs', element: withSuspense(<ApiDocsPage />) },
     ],
   },