feat(admin): bump react-router and adapt new routes package (#11887)

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit

- **New Features**
  - Added new admin routes: "auth", "setup", and "notFound" for improved navigation and access within the admin interface.
  - Introduced a utility for simplified and flexible lazy loading of React components with fallback support.

- **Improvements**
  - Updated routing structure in the admin frontend for clearer route management and enhanced Sentry integration.
  - Centralized route definitions for easier maintenance and consistency.
  - Upgraded dependencies to support the latest React Router and React versions.
  - Enhanced asynchronous handling in setup form navigation.

- **Chores**
  - Updated project references and workspace dependencies for better package management.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/routes/routes.json

@@ -5,6 +5,8 @@
     "admin": {
       "route": "admin",
       "children": {
+        "auth": "auth",
+        "setup": "setup",
         "accounts": "accounts",
         "ai": "ai",
         "settings": {