fix: 产品导入去重 — 批次内product_code去重 + DB层按product_code+org_id兜底查重

- 批次内seen_codes去重: 同一导入批次中相同product_code只处理第一条
- DB查重增加fallback: resource_ref_id查不到时再按product_code+org_id查
- update时同步写入resource_ref_id

product_management/core.py

@@ -1172,13 +1172,21 @@ class ProductManager:
                 created_cats += 1
 
             # Step 3: Process products — update existing, create new
+            # Local dedup: skip duplicate product_code within same import batch
+            seen_codes = set()
             for prod in products:
                 target_cat_id = source_to_id.get(prod.get('source_category_id'))
                 if not target_cat_id:
                     continue
 
+                product_code = prod.get('product_code', '')
                 resource_ref_id = prod.get('resource_ref_id', '')
 
+                # Skip duplicate product_code in this batch
+                if product_code in seen_codes:
+                    continue
+                seen_codes.add(product_code)
+
                 # Check if product already exists by resource_ref_id + org_id
                 existing_prod = None
                 if resource_ref_id:
@@ -1188,15 +1196,24 @@ class ProductManager:
                         {'ref_id': resource_ref_id, 'org_id': org_id}
                     )
 
+                # Fallback: check by product_code + org_id (unique constraint)
+                if not existing_prod and product_code:
+                    existing_prod = await sor.sqlExe(
+                        """SELECT id FROM product
+                           WHERE product_code = ${code}$ AND org_id = ${org_id}$""",
+                        {'code': product_code, 'org_id': org_id}
+                    )
+
                 if existing_prod:
                     # Update existing product
                     await sor.U('product', {
                         'id': existing_prod[0].id,
                         'product_name': prod.get('product_name', ''),
-                        'product_code': prod.get('product_code', ''),
+                        'product_code': product_code,
                         'product_type': prod.get('product_type', ''),
                         'brief_intro': prod.get('brief_intro', ''),
                         'category_id': target_cat_id,
+                        'resource_ref_id': resource_ref_id,
                         'sort_order': str(prod.get('sort_order', 0)),
                         'updated_at': now
                     })