- Introduced constants for admin hooks: `STATS_FETCH_LIMIT`, `DEFAULT_PAGE_LIMIT`, and `STATS_REFETCH_INTERVAL` to enhance readability and maintainability.
- Updated query guards to ensure data fetching is restricted to superusers.
- Enhanced accessibility across admin components by adding `aria-hidden` attributes and improving focus-visible styles.
- Simplified `useAdminStats`, `useAdminUsers`, and `useAdminOrganizations` with shared constants.
- Added 403 Forbidden page with proper structure, styling, and tests.
- Implemented new tests for admin hooks, DashboardStats, AdminLayout, and ForbiddenPage for better coverage.
- 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.
