fix: auto-fix code issues (cron)

- 修复重复导入/字段 (llm_client.py 中的重复注释)
- 修复PEP8格式问题 (E501行长度超过100字符)
- 修复多行SQL语句和字符串格式化
- 修复f-string过长问题

涉及文件:
- backend/developer_ecosystem_manager.py
- backend/document_processor.py
- backend/enterprise_manager.py
- backend/export_manager.py
- backend/growth_manager.py
- backend/llm_client.py
- backend/localization_manager.py
- backend/main.py
- backend/neo4j_manager.py
- backend/ops_manager.py
- backend/performance_manager.py
- backend/plugin_manager.py
- backend/search_manager.py
- backend/security_manager.py
- backend/subscription_manager.py
- backend/tenant_manager.py
- backend/test_phase8_task6.py
- backend/test_phase8_task8.py
- backend/tingwu_client.py
- backend/workflow_manager.py

backend/test_phase8_task6.py

@@ -513,7 +513,8 @@ class TestDeveloperEcosystem:
                 self.manager.update_developer_stats(self.created_ids["developer"][0])
                 profile = self.manager.get_developer_profile(self.created_ids["developer"][0])
                 self.log(
-                    f"Updated developer stats: {profile.plugin_count} plugins, {profile.template_count} templates",
+                    f"Updated developer stats: {profile.plugin_count} plugins, "
+                    f"{profile.template_count} templates",
                 )
         except Exception as e:
             self.log(f"Failed to update developer stats: {e!s}", success=False)