fix: scheduled_at input — store raw datetime-local value, convert on save

src/admin/orders/OrderModal.jsx

@@ -50,7 +50,7 @@ const OrderModal = ({ order, onClose, onSaved, mode = 'edit' }) => {
     telegram_username: order?.telegram_username || '',
     max_username: order?.max_username || '',
     address: order?.address || '',
-    scheduled_at: order?.scheduled_at || '',
+    scheduled_at: order?.scheduled_at ? new Date(order.scheduled_at).toISOString().slice(0, 16) : '',
   });
   const [events, setEvents] = useState([]);
   const { photos, uploading, uploadPhotos, deletePhoto } = useOrderPhotos(mode === 'edit' ? order?.id : null);
@@ -94,7 +94,7 @@ const OrderModal = ({ order, onClose, onSaved, mode = 'edit' }) => {
     ...f,
     area_sqm: f.area_sqm === '' ? null : Number(f.area_sqm),
     final_cost: f.final_cost === '' ? null : Number(f.final_cost),
-    scheduled_at: f.scheduled_at === '' ? null : f.scheduled_at,
+    scheduled_at: f.scheduled_at === '' ? null : new Date(f.scheduled_at).toISOString(),
   });
 
   const handleShare = () => {
@@ -281,8 +281,8 @@ const OrderModal = ({ order, onClose, onSaved, mode = 'edit' }) => {
               id="modal-scheduled"
               type="datetime-local"
               name="scheduled_at"
-              value={form.scheduled_at ? new Date(form.scheduled_at).toISOString().slice(0, 16) : ''}
-              onChange={(e) => setForm((prev) => ({ ...prev, scheduled_at: e.target.value ? new Date(e.target.value).toISOString() : '' }))}
+              value={form.scheduled_at}
+              onChange={(e) => setForm((prev) => ({ ...prev, scheduled_at: e.target.value }))}
               style={inputStyle}
             />
           </div>