feat(cupang): 상자 목록을 번호·제품명·제품코드·수량 표로, 엑셀 다운로드 추가

- ② 상자 목록: 카드 대신 표. 한 상자에 여러 제품이면 상자번호 칸 rowspan 병합
- GET /cupang/{id}/boxes.xlsx — 같은 표를 xlsx 로 (export.build_box_list_workbook)
- box_list 항목에 product_code 포함

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

app/modules/cupang/router.py

@@ -431,6 +431,47 @@ async def detail(request: Request, shipment_id: int) -> HTMLResponse:
     )
 
 
+@router.get("/{shipment_id:int}/boxes.xlsx")
+async def export_box_list_xlsx(request: Request, shipment_id: int) -> Any:
+    """상자 목록(상자번호·제품명·제품코드·수량) 엑셀 다운로드."""
+    from io import BytesIO  # noqa: WPS433
+
+    from fastapi.responses import StreamingResponse  # noqa: WPS433
+
+    from .export import build_box_list_workbook  # noqa: WPS433
+
+    guard = _guard(request)
+    if not isinstance(guard, tuple):
+        return guard
+    store, _user = guard
+
+    ship = store.get_shipment(shipment_id=shipment_id)
+    if not ship:
+        raise HTTPException(status_code=404, detail="출고 묶음을 찾을 수 없습니다.")
+
+    items = [
+        {
+            "product_code": ln.get("product_code"),
+            "product_name": ln.get("product_name_snapshot") or ln.get("product_code"),
+            "quantity": int(ln.get("quantity") or 0),
+        }
+        for ln in (ship.get("lines") or [])
+    ]
+    box_list = _expand_box_list(ship, _compute_boxes(store, items), items)
+
+    wb = build_box_list_workbook(ship, box_list)
+    buf = BytesIO()
+    wb.save(buf)
+    buf.seek(0)
+    stamp = str(ship.get("ship_date") or "").replace("-", "")
+    filename = f"{stamp}_cupang_boxes_{shipment_id}.xlsx"
+    return StreamingResponse(
+        buf,
+        media_type="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
+        headers={"Content-Disposition": f'attachment; filename="{filename}"'},
+    )
+
+
 def _safe_next(raw: str, fallback: str) -> str:
     """열린 리다이렉트 방지 — /cupang/ 안쪽 경로만 허용."""
     nxt = (raw or "").strip()
@@ -1077,6 +1118,7 @@ def _expand_box_list(
                 contents = [
                     {
                         "product_name": it.get("product_name") or it.get("product_code") or "",
+                        "product_code": it.get("product_code") or "",
                         "quantity": int(it.get("quantity") or 0),
                     }
                     for it in (entry.get("items") or [])
@@ -1087,7 +1129,11 @@ def _expand_box_list(
             else:
                 code = str(entry.get("product_code") or "")
                 contents = [
-                    {"product_name": entry.get("name") or code, "quantity": units}
+                    {
+                        "product_name": entry.get("name") or code,
+                        "product_code": code,
+                        "quantity": units,
+                    }
                 ]
                 box_name = box_name_by_code.get(code, "")
                 for _ in range(count):
@@ -1102,7 +1148,11 @@ def _expand_box_list(
                         "kind": "product",
                         "box_name": r.get("box_name") or "",
                         "items": [
-                            {"product_name": r["product_name"], "quantity": r["units_per_box"]}
+                            {
+                                "product_name": r["product_name"],
+                                "product_code": r["product_code"],
+                                "quantity": r["units_per_box"],
+                            }
                         ],
                     }
                 )
@@ -1115,6 +1165,7 @@ def _expand_box_list(
                         "items": [
                             {
                                 "product_name": it.get("product_name") or "",
+                                "product_code": it.get("product_code") or "",
                                 "quantity": int(it.get("quantity") or 0),
                             }
                             for it in (box.get("items") or [])