fix(cookie-gate): 必需 cookie 改全量校验并收紧各账号必需名单

required_cookie_names 原语义是「任一必需名命中即有效」，单个匿名 cookie
（如小红书 a1）就能把游客会话判为有效；改为全部必需名都存在、存活且域名
匹配才算通过。随之按实际登录产物收紧名单：jd 去 pin、erp321 留
u_id+u_co_id、小红书改 customer-sso-sid+solar.beaker.session.id、
星图仅 sid_guard。cookie_gate 用例冻结时钟改相对时钟防过期漂移。

tests/test_cookie_gate.py

@@ -28,7 +28,7 @@ from gyxx_flow.workflow.engine import WorkflowEngine
 from gyxx_flow.workflow.model import StepDefinition, WorkflowDefinition
 from gyxx_flow.workflow.steps import StepExecution
 
-_NOW = datetime(2026, 10, 8, 12, 0, 0, tzinfo=timezone.utc)
+_NOW = datetime.now(timezone.utc).replace(microsecond=0)
 
 
 def _settings(tmp_path: Path) -> Settings: