- Introduced `useAdminStats`, `useAdminUsers`, and `useAdminOrganizations` hooks for admin data fetching with React Query.
- Added `AdminSidebar`, `Breadcrumbs`, and related navigation components for the admin section.
- Implemented comprehensive unit and integration tests for admin components.
- Created E2E tests for admin access control, navigation, and dashboard functionality.
- Updated exports to include new admin components.
