fix: 客户列表多 primary 经理时顿号连接显示(修复字典覆盖)

- mgr_map 由字典推导式改为按 customer_id 聚合 list,再用顿号连接
- 修复同一客户多个 primary 经理时,后写入覆盖先写入导致只显示一个名字

数据修复: 大化瑶族自治县公安局交通警察大队 移除韦柳柏的 primary 分配,唐晓静为唯一 primary

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

backend/app/api/customers.py

@@ -103,10 +103,14 @@ async def list_customers(
             select(CustomerAssignment.customer_id, User.name)
             .join(User, CustomerAssignment.manager_id == User.id)
             .where(CustomerAssignment.customer_id.in_([c.id for c in items]), CustomerAssignment.role == "primary")
+            .order_by(CustomerAssignment.customer_id)
         )
-        mgr_map = {str(cid): name for cid, name in mgr_result.all()}
+        mgr_map: dict[str, list] = {}
+        for cid, name in mgr_result.all():
+            mgr_map.setdefault(str(cid), []).append(name)
         for item in items:
-            item.primary_manager_name = mgr_map.get(str(item.id), None)
+            names = mgr_map.get(str(item.id), [])
+            item.primary_manager_name = "、".join(names) if names else None
 
     return CustomerListResponse(
         items=items,