Round 3 fixes: cancelled polling, aggregator invalid_count, filter state, scheduler atomicity, HTTP exception handler, tests

tests/conftest.py

@@ -85,12 +85,14 @@ async def sample_proxy(db, proxy_repo):
 
 
 @pytest_asyncio.fixture(autouse=True)
-async def mock_external_requests(monkeypatch):
+async def mock_external_requests(monkeypatch, request):
     """
-    自动在所有测试中 mock 外部网络请求：
+    自动在集成/E2E 测试中 mock 外部网络请求：
     1. 插件爬取返回固定测试代理，避免真实 HTTP 请求
     2. 代理验证瞬间成功，避免连接超时等待
     """
+    if "/unit/" in request.node.nodeid:
+        return
     from app.services.plugin_runner import PluginRunner
     from app.services.validator_service import ValidatorService