feat(treatment): date-range filter on treatment cases, and time on the start stamp

The list could be narrowed by status and by search but not by when a case
opened, which is the one axis a clinic actually reports on. `from` and `to`
(YYYY-MM-DD) now bound `opened_at`, using the same strtotime day-boundary
convention the appointment date filters already use under the app's global
Tehran timezone. A malformed value is ignored rather than erroring — this is a
filter, not a form field.

Both bounds live in the URL via useUrlState, so back and refresh keep the range.
The two date inputs and the "تا" between them are one nowrap unit; letting them
wrap separately orphaned the word from its field on a 390px screen.

The card's "شروع" showed only the Jalali date, so several cases opened on the
same day were indistinguishable on that line too. It now uses formatDateTime.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

assets/admin/pages/TreatmentCasesPage.test.tsx

@@ -102,6 +102,28 @@ describe('صفحهٔ پرونده‌های درمان', () => {
     expect(screen.queryByText(/پرونده‌ای یافت نشد/)).not.toBeInTheDocument();
   });
 
+  it('بازهٔ تاریخ به‌صورت from و to می‌رود', async () => {
+    mockList([caseRow()]);
+
+    renderWithProviders(<TreatmentCasesPage />);
+    await screen.findByText('محمد رسولی');
+
+    // PersianDateInput تریگرش input نیست، پس با نام دسترس‌پذیرش پیدایش می‌کنیم.
+    fireEvent.click(screen.getByLabelText('شروع از تاریخ'));
+
+    expect(screen.getByLabelText('شروع تا تاریخ')).toBeInTheDocument();
+  });
+
+  it('تاریخ شروع ساعت هم دارد', async () => {
+    mockList([caseRow({ opened_at: 1_786_000_000 })]);
+
+    renderWithProviders(<TreatmentCasesPage />);
+
+    // formatDateTime ساعت را با «:» می‌آورد؛ formatDate نمی‌آورد.
+    const start = await screen.findByText(/^شروع:/);
+    expect(start.textContent).toMatch(/:/);
+  });
+
   it('دکمهٔ ویرایش مودال را باز می‌کند', async () => {
     mockList([caseRow()]);