Direct navigation to /admin/clients/{id} now:
- Fetches GET /api/clients/{id} on mount (unconditional)
- Fetches GET /api/pets?clientId= on mount
- Shows loading state while fetching
- Shows error state on failure (401/404/5xx)
- Preserves existing link-based navigation from ClientsPage
Added ClientDetailPage.tsx as a standalone route component.
Added 3 E2E tests covering direct nav, loading state, and error state.
Co-Authored-By: Paperclip <noreply@paperclip.ing>