feat(HEL-490): 剩余行情改由数据中枢主线路提供

正式页面以 8766 为主线路，旧接口只作故障备用；compose 钉死全部 DATAHUB_READ_*，避免现网残留 0 造成假完成。

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: multica-agent <github@multica.ai>

tests/test_realtime_dashboard.py

@@ -364,6 +364,23 @@ class RealtimeDashboardTests(unittest.TestCase):
         self.assertEqual(quote["amount"], 406050000)
         self.assertEqual(quote["source"], "tencent_qt")
 
+    def test_datahub_market_quotes_used_before_legacy(self):
+        calls = []
+
+        def try_market_quotes(trade_date):
+            calls.append(trade_date)
+            return list(FREE_QUOTES)
+
+        self.client.try_market_quotes = try_market_quotes
+        self.client.realtime_aggregator = FakeFreeAggregator(fail=True)
+        TushareClient._realtime_reference_cache.clear()
+        dashboard = self.client._realtime_dashboard("20260720", "20260720", "20260717")
+        self.assertEqual(calls, ["20260720"])
+        self.assertEqual(dashboard["meta"]["quote_source"], "datahub")
+        self.assertEqual(dashboard["meta"]["source"], "datahub")
+        self.assertEqual(dashboard["meta"]["quote_count"], 3)
+        self.assertIn("数据中枢", dashboard["meta"]["notice"])
+
 
 if __name__ == "__main__":
     unittest.main()