Hide manual trade by default, block open while running, auto-refresh auth token.

Also fix flat-side reconcile to check both long and short residuals; document in 更新说明.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/strategy/engine.py

@@ -128,6 +128,9 @@ class StrategyEngine:
             "sim": s.is_sim,
             "live_ready": (live_ready()[0] if not s.is_sim else True),
             "live_ready_reason": (live_ready()[1] if not s.is_sim else "sim"),
+            "show_manual_trade_buttons": self.ledger.get_setting_bool(
+                "show_manual_trade_buttons", False
+            ),
         }
 
     def _set_state(self, **kwargs: Any) -> None: