feat: implement useUrlState hook for managing URL-based state in admin pages

- Refactor multiple admin pages (BlogsPage, ClinicsPage, DoctorsPage, etc.) to utilize the new useUrlState hook for managing pagination, search, and filter states via URL.
- Ensure that the state persists in the URL, allowing users to return to the same state when navigating back from detail pages.
- Update relevant components to handle state changes appropriately and maintain clean URLs by removing default values.
- Add SlotPicker component for selecting appointment slots based on availability.
- Create tests for useUrlState to validate its functionality and ensure correct behavior when interacting with the URL.
- Update API documentation to reflect changes in appointment creation and slot selection processes.

assets/admin/pages/UsersPage.tsx

@@ -8,6 +8,7 @@ import {
 } from '@heroicons/react/24/outline';
 import { toast } from 'sonner';
 import { api } from '../lib/api';
+import { useUrlState, pageOf } from '../hooks/useUrlState';
 import Portal from '../components/ui/Portal';
 import type { ApiResponse, PaginatedResponse } from '../lib/api';
 import { formatDate, formatNumber, maskMobile } from '../lib/utils';
@@ -170,22 +171,27 @@ export default function UsersPage() {
   const navigate = useNavigate();
   const qc = useQueryClient();
 
-  const [page, setPage]               = useState(1);
+  // وضعیت لیست در URL می‌ماند تا «بازگشت» از پروفایل کاربر، همین فیلترها و صفحه را برگرداند.
+  const [urlState, setUrlState] = useUrlState({ page: '1', search: '', role: '', status: '' });
+  const page   = pageOf(urlState.page);
+  const search = urlState.search;
+  const role   = urlState.role;
+  const status = urlState.status;
+  const setPage   = (p: number) => setUrlState({ page: String(p) });
+  const setRole   = (v: string) => setUrlState({ role: v, page: '1' });
+  const setStatus = (v: string) => setUrlState({ status: v, page: '1' });
+
   const [limit]                       = useState(25);
-  const [searchInput, setSearchInput] = useState('');
-  const [search, setSearch]           = useState('');
-  const [role, setRole]               = useState('');
-  const [status, setStatus]           = useState('');
+  // فیلد جستجو local می‌ماند (تایپ روان)؛ مقدارِ debounce‌شده به URL می‌رود.
+  const [searchInput, setSearchInput] = useState(urlState.search);
   const [deleteTarget, setDeleteTarget] = useState<AdminUser | null>(null);
   const [roleTarget, setRoleTarget]     = useState<AdminUser | null>(null);
 
   useEffect(() => {
-    const t = setTimeout(() => { setSearch(searchInput); setPage(1); }, 350);
+    const t = setTimeout(() => setUrlState({ search: searchInput, page: '1' }), 350);
     return () => clearTimeout(t);
   }, [searchInput]);
 
-  useEffect(() => { setPage(1); }, [role, status]);
-
   // ── Queries ──
 
   const statsQ = useQuery({