chore: ruff 代码检查与修复

130 issues auto-fixed (import ordering, UP045/UP006 type annotations),
33 issues manually fixed (E712/E501/E402/E722 + N818 rename + per-file
wechat ignore for N8xx naming conventions). All 33 tests pass.

tests/test_crawler/test_dahuagov_spider.py

@@ -1,7 +1,9 @@
+from unittest.mock import AsyncMock, MagicMock, patch
+
 import pytest
-from unittest.mock import AsyncMock, patch, MagicMock
-from app.crawler.dahuagov_spider import DahuagovSpider
+
 from app.crawler.base import PipelineConfig
+from app.crawler.dahuagov_spider import DahuagovSpider
 
 
 @pytest.mark.asyncio