fix(appointments): stay on the same day after edit/create

AppointmentsPage now reads an optional ?date=YYYY-MM-DD query param as its
initial selected date. AppointmentEditPage and AppointmentCreatePage navigate
back to /admin/appointments?date=<the appointment's day> on save (and the edit
page's back link carries the date too), so the user returns to the day they
were viewing instead of today.

Test: AppointmentsPage honors ?date= and fetches that day.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

assets/admin/pages/AppointmentsPage.tsx

@@ -1,6 +1,6 @@
 import React, { useEffect, useRef, useState } from 'react';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
-import { useNavigate } from 'react-router-dom';
+import { useNavigate, useSearchParams } from 'react-router-dom';
 import {
   PlusIcon, ChevronRightIcon, ChevronLeftIcon, CalendarDaysIcon,
   AdjustmentsHorizontalIcon,
@@ -200,8 +200,10 @@ export default function AppointmentsPage() {
   const isDoctor = primaryRole === 'doctor';
   const isRepresentation = primaryRole === 'representation';
 
+  const [params] = useSearchParams();
   const today = new Date().toISOString().slice(0, 10);
-  const [selectedDate, setSelectedDate] = useState(today);
+  // پس از ویرایش/ثبت، صفحه با ?date=... باز می‌شود تا همان روز نمایش داده شود.
+  const [selectedDate, setSelectedDate] = useState(params.get('date') || today);
   const [viewMode, setViewMode] = useState<TurnsViewMode>('timeline');
   const [selectedDoctorUuid, setSelectedDoctorUuid] = useState<string>(isDoctor && dbUuid ? dbUuid : '');
   const [bookingSlot, setBookingSlot] = useState<BookingSlot | null>(null);