chore(lint): make the repository ruff-clean under the strict select

Clear the deferred full-repo lint backlog so the whole tree passes the strict
ruff select (E,W,F,I,B,UP,C4,SIM). Mechanical fixes dominate: import sorting,
pep585/604 annotations, dropped dead imports, and whitespace. The few semantic
changes are behavior-preserving: declare __all__ on the agent_utils and
alpha_vantage re-export hubs; expand 'from x import *' to explicit names; use
immutable tuple defaults instead of mutable list defaults; contextlib.suppress
for try/except/pass; and narrow an over-broad assertRaises.

tradingagents/agents/utils/news_data_tools.py

@@ -1,7 +1,10 @@
+from typing import Annotated
+
 from langchain_core.tools import tool
-from typing import Annotated, Optional
+
 from tradingagents.dataflows.interface import route_to_vendor
 
+
 @tool
 def get_news(
     ticker: Annotated[str, "Ticker symbol"],
@@ -23,8 +26,8 @@ def get_news(
 @tool
 def get_global_news(
     curr_date: Annotated[str, "Current date in yyyy-mm-dd format"],
-    look_back_days: Annotated[Optional[int], "Days to look back; omit to use the configured default"] = None,
-    limit: Annotated[Optional[int], "Max articles to return; omit to use the configured default"] = None,
+    look_back_days: Annotated[int | None, "Days to look back; omit to use the configured default"] = None,
+    limit: Annotated[int | None, "Max articles to return; omit to use the configured default"] = None,
 ) -> str:
     """
     Retrieve global news data.