style(backend): ruff format 统一此前批次的排版残留

纯排版无行为变化（ruff format 重排 7 个此前批次的文件），
涉及模块集成回归全绿（67 passed）。

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

backend/tests/integration/test_customers.py

@@ -151,9 +151,7 @@ class TestCrudFlow:
         assert dup.status_code == 400, dup.text
         assert "该公司名称与负责人的客户已存在" in dup.json()["message"]
 
-    def test_删除被业务引用的客户_400引导处理单据(
-        self, client: TestClient, normal: dict
-    ) -> None:
+    def test_删除被业务引用的客户_400引导处理单据(self, client: TestClient, normal: dict) -> None:
         """业务表就位后删除保护补齐：FK RESTRICT 不能以 500 暴露。"""
         headers = normal["headers"]
         customer = _create_customer(client, headers)

backend/tests/integration/test_personnel.py

@@ -235,7 +235,9 @@ class TestDeleteProtection:
         member = _create(client, headers, manager_id=manager["id"])  # 团队成员占用
         blocked = client.delete(f"{_PERSONNEL}/{manager['id']}", headers=headers)
         assert blocked.status_code == 400, blocked.text
-        assert "存在团队成员、客户归属或业务归属引用，请改为离职而非删除" in blocked.json()["message"]
+        assert (
+            "存在团队成员、客户归属或业务归属引用，请改为离职而非删除" in blocked.json()["message"]
+        )
 
         client.delete(f"{_PERSONNEL}/{member['id']}", headers=headers)
         freed = client.delete(f"{_PERSONNEL}/{manager['id']}", headers=headers)
@@ -261,7 +263,9 @@ class TestDeleteProtection:
 
         blocked = client.delete(f"{_PERSONNEL}/{owner['id']}", headers=headers)
         assert blocked.status_code == 400, blocked.text
-        assert "存在团队成员、客户归属或业务归属引用，请改为离职而非删除" in blocked.json()["message"]
+        assert (
+            "存在团队成员、客户归属或业务归属引用，请改为离职而非删除" in blocked.json()["message"]
+        )
 
         # 保护与在职状态无关：离职并不能让物理删除放行
         client.put(f"{_PERSONNEL}/{owner['id']}/status", json={"status": 0}, headers=headers)
@@ -273,9 +277,7 @@ class TestDeleteProtection:
         freed = client.delete(f"{_PERSONNEL}/{owner['id']}", headers=headers)
         assert freed.status_code == 200, freed.text
 
-    def test_被业务归属引用禁删_负责或协助任一即拦(
-        self, client: TestClient, normal: dict
-    ) -> None:
+    def test_被业务归属引用禁删_负责或协助任一即拦(self, client: TestClient, normal: dict) -> None:
         """业务表就位后删除保护补齐：负责/协助引用任一即拦，FK 不以 500 暴露。"""
         headers = normal["headers"]
         owner = _create(client, headers)