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

internal/web/translation/en-US.json

@@ -112,6 +112,8 @@
     "hosts": "Hosts",
     "settings": "Panel Settings",
     "xray": "Xray Configs",
+    "routing": "Routing",
+    "outbounds": "Outbounds",
     "apiDocs": "API Docs",
     "logout": "Log Out",
     "link": "Manage",