feat: redesign appointments (نوبت‌ها) admin UI to match tauri turns + expandable sidebar

Rebuild the /admin/appointments page visual layer to match the tauri
clinic-pro-tauri "turns" design while keeping all existing data wiring and
backend endpoints unchanged (add/edit/move/transfer-reserve/replace already
supported via PATCH /api/v1/appointment/{uuid} and POST /api/v1/my/appointment).

Frontend (assets/admin):
- Sidebar: نوبت‌ها becomes an expandable parent with sub-items
  «نوبت های تایید شده» (/admin/appointments) and «افزودن نوبت»
  (/admin/appointments/new); auto-expands on active child. Applied to
  admin/clinic/doctor/secretary roles. Adds nav-subitem styling.
- New presentational components under components/appointments/: tauri status
  palette (turnStatus), TurnsStatInfo, TurnsViewToggle (sliding), DoctorTabs
  (underline), TurnsTimeline (marker rail + status cards, empty slot → افزودن
  نوبت), TurnsTable.
- AppointmentsPage recomposed with the new components (stats bar, doctor tabs,
  view toggle, timeline/table), preserving queries, filters, pagination,
  quick-book modal and the row actions menu.
- AppointmentCreatePage: full-page create form (CreateTurn layout) at
  /admin/appointments/new, reusing POST /api/v1/my|admin/appointment.

Tests: TurnsStatInfo, TurnsTimeline, Sidebar (expandable), AppointmentsPage,
AppointmentCreatePage. Backend move/reserve/replace verified green via existing
tests/Appointment/AppointmentUpdateTest + AppointmentWorkflowFieldsTest.

No API endpoints changed → no docs/api change.

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

assets/admin/components/appointments/DoctorTabs.tsx

@@ -0,0 +1,50 @@
+/**
+ * تب دکترها با نشانگر underline — بازسازی تب‌های بالای صفحهٔ نوبت‌های طرح tauri
+ * (`index.jsx`): فعال #5559ce با خط زیرین، بقیه خاکستری.
+ */
+export interface DoctorTab {
+  uuid: string;
+  name: string;
+}
+
+export default function DoctorTabs({
+  doctors, selected, onSelect, showAll = true,
+}: {
+  doctors: DoctorTab[];
+  /** '' یعنی «همه». */
+  selected: string;
+  onSelect: (uuid: string) => void;
+  showAll?: boolean;
+}) {
+  const tabs: DoctorTab[] = showAll ? [{ uuid: '', name: 'همه' }, ...doctors] : doctors;
+  return (
+    <div style={{
+      display: 'flex', alignItems: 'center', gap: 24, padding: '4px 4px 0',
+      borderBottom: '1px solid var(--border)', overflowX: 'auto', marginBottom: 16,
+    }}>
+      {tabs.map((d) => {
+        const active = selected === d.uuid;
+        return (
+          <button
+            key={d.uuid || 'all'}
+            type="button"
+            onClick={() => onSelect(d.uuid)}
+            style={{
+              position: 'relative', background: 'none', border: 'none', cursor: 'pointer',
+              fontFamily: 'inherit', fontSize: 15, fontWeight: 500, padding: '8px 2px 12px',
+              color: active ? 'var(--primary)' : 'var(--text-2)', whiteSpace: 'nowrap',
+            }}
+          >
+            {d.name}
+            {active && (
+              <span style={{
+                position: 'absolute', bottom: -1, left: 0, right: 0, height: 3,
+                background: 'var(--primary)', borderRadius: '3px 3px 0 0',
+              }} />
+            )}
+          </button>
+        );
+      })}
+    </div>
+  );
+}