fix(dispatch): Shopee Packing List xlsx 파싱 추가

- 헤더 별칭에 underscore형(order_sn, tracking_number) 추가
- Shopee 는 SKU/수량이 product_info 한 셀에 묶여 있어 전용 파서 추가
  · store.parse_shopee_product_info: [n] 단위 상품 분해, SKU/상품명/수량 추출
  · parser._parse_shopee: 1행=1주문=1박스, 상품 펼쳐 박스로 묶음, 배송사 SPX 추론
- parse_export(platform) 로 Shopee/일반 경로 분기, 라우터가 platform 전달
- 이름/주소/전화는 xlsx 에 없음 → 라벨 PDF 단계에서 보강 예정
- 테스트 3개 추가

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/modules/dispatch/tests/test_grouping.py

@@ -81,6 +81,34 @@ def test_column_alias_strip_and_case():
     assert "seller_sku" in mapping
 
 
+def test_shopee_product_info_single():
+    blob = ("[1] Product Name:[1+1=3] Mira's Kitchen Korean Grade Miracle Food "
+            "Container Launch PROMO; Variation Name:3x 320ml; Price: RM 20.00; "
+            "Quantity: 1; SKU Reference No.: MT-0320_3;")
+    items = store.parse_shopee_product_info(blob)
+    assert len(items) == 1, items
+    it = items[0]
+    assert it["seller_sku"] == "MT-0320_3", it
+    assert it["quantity"] == 1, it
+    assert it["variation"] == "3x 320ml", it
+    assert "Mira's Kitchen" in it["product_name"], it
+
+
+def test_shopee_product_info_multi():
+    blob = ("[1] Product Name:Item A; Variation Name:S; Quantity: 2; "
+            "SKU Reference No.: MT-0001; "
+            "[2] Product Name:Item B; Variation Name:L; Quantity: 3; "
+            "SKU Reference No.: MX-0002;")
+    items = store.parse_shopee_product_info(blob)
+    skus = {i["seller_sku"]: i["quantity"] for i in items}
+    assert skus == {"MT-0001": 2, "MX-0002": 3}, skus
+
+
+def test_shopee_product_info_empty():
+    assert store.parse_shopee_product_info("") == []
+    assert store.parse_shopee_product_info(None) == []
+
+
 def _run_all():
     fns = [v for k, v in sorted(globals().items()) if k.startswith("test_") and callable(v)]
     for fn in fns: