fix(yahoo): report an unreachable Yahoo on insider transactions as unavailable

- the outage raised for an empty insider table reaches the router as a vendor error, not as a symbol with no data

tests/test_no_data_handling.py

@@ -91,3 +91,15 @@ class TestRouteToVendorSentinel(unittest.TestCase):
 
 if __name__ == "__main__":
     unittest.main()
+
+
+@pytest.mark.unit
+def test_an_unreachable_yahoo_is_not_reported_as_a_symbol_without_insider_data():
+    from tradingagents.dataflows.errors import VendorRateLimitError
+    from tradingagents.dataflows.vendors.yahoo import fundamentals
+
+    ticker = type("T", (), {"insider_transactions": pd.DataFrame()})()
+    with mock.patch.object(fundamentals.yf, "Ticker", return_value=ticker), \
+         mock.patch.object(fundamentals, "vendor_reachable", return_value=False), \
+         pytest.raises(VendorRateLimitError):
+        fundamentals.get_insider_transactions("AAPL", curr_date="2026-09-21")

tradingagents/dataflows/vendors/yahoo/fundamentals.py

@@ -184,6 +184,8 @@ def get_insider_transactions(
 
         return f"# Insider Transactions data for {canonical}\n" + _TRANSACTION_DATE_VINTAGE + data.to_csv()
 
+    except VendorError:
+        raise
     except Exception as e:
         raise NoMarketDataError(ticker, canonical, f"insider transactions unavailable: {e}") from e