fix(account): 优化止损和止盈价格获取逻辑

在账户模块中，改进了止损和止盈价格的获取逻辑，确保在无数据库记录时能够根据币安持仓和配置比例进行计算。同时，增强了异常处理，确保在无法确定止损止盈价时提供详细的错误信息。这一改动旨在提升风险控制能力和系统的稳定性。

backend/api/routes/account.py

@@ -80,18 +80,32 @@ async def _ensure_exchange_sltp_for_symbol(symbol: str, account_id: int = 1):
         except Exception:
             mark_price = None
 
-        # 4) 从数据库 open trade 取止损/止盈价（优先取最近一条）
+        # 4) 止损/止盈价：优先从数据库 open trade 取；无 DB 记录时用币安持仓 + 配置比例计算（支持手动开仓补挂）
         from database.models import Trade
         open_trades = Trade.get_by_symbol(symbol, status='open', account_id=account_id) or []
-        if not open_trades:
-            raise HTTPException(status_code=400, detail=f"{symbol} 数据库无 open 交易记录，无法确定止损止盈价")
-        # 尽量取最新一条 open trade（避免同一symbol多条 open 时取到旧记录）
+        sl = None
+        tp = None
+        entry_price = float(p0.get("entryPrice", 0) or 0)
+        qty = abs(float(amt))
+        lv = float(p0.get("leverage", 0) or 0) or 10.0
+
+        def _ratio(v, default):
+            try:
+                x = float(v)
+                if x > 1:
+                    x = x / 100.0
+                if x < 0:
+                    x = default
+                return x
+            except Exception:
+                return default
+
+        if open_trades:
             try:
                 open_trades.sort(key=lambda x: int(x.get("id", 0) or 0), reverse=True)
             except Exception:
                 pass
             trade = open_trades[0]
-
             sl = trade.get("stop_loss_price")
             tp = trade.get("take_profit_2") or trade.get("take_profit_price") or trade.get("take_profit_1")
             try:
@@ -102,48 +116,35 @@ async def _ensure_exchange_sltp_for_symbol(symbol: str, account_id: int = 1):
                 tp = float(tp) if tp is not None else None
             except Exception:
                 tp = None
-
-        # 兼容旧数据库：如果 trades 表还没迁移 stop_loss_price / take_profit_price 字段，
-        # 则回退用 entry_price/quantity/leverage + 配置的 STOP_LOSS_PERCENT/TAKE_PROFIT_PERCENT 计算。
-        if not sl or not tp:
-            try:
+            if entry_price <= 0 or qty <= 0:
                 entry_price = float(trade.get("entry_price") or 0)
                 qty = float(trade.get("quantity") or 0)
-                lv = float(trade.get("leverage") or 0) or float(p0.get("leverage") or 0) or 10.0
+                lv = float(trade.get("leverage") or 0) or lv
+
+        # 无 DB 记录或 DB 中 sl/tp 为空：用币安持仓的 entry/quantity/leverage + 配置比例计算
+        if not sl or not tp:
+            try:
                 if entry_price <= 0 or qty <= 0 or lv <= 0:
                     raise ValueError("entry_price/quantity/leverage invalid")
-
-                def _ratio(v, default):
-                    try:
-                        x = float(v)
-                        # 兼容：若误存成 5（表示5%），则转为 0.05
-                        if x > 1:
-                            x = x / 100.0
-                        if x < 0:
-                            x = default
-                        return x
-                    except Exception:
-                        return default
-
                 sl_pct = _ratio(TradingConfig.get_value("STOP_LOSS_PERCENT", 0.05), 0.05)
                 tp_pct = _ratio(TradingConfig.get_value("TAKE_PROFIT_PERCENT", 0.15), 0.15)
-
                 notional = entry_price * qty
                 margin = notional / lv
                 sl_amount = margin * sl_pct
                 tp_amount = margin * tp_pct
-
                 if side == "BUY":
                     sl = entry_price - (sl_amount / qty)
                     tp = entry_price + (tp_amount / qty)
                 else:
                     sl = entry_price + (sl_amount / qty)
                     tp = entry_price - (tp_amount / qty)
-
                 if not sl or not tp or sl <= 0 or tp <= 0:
                     raise ValueError("computed sl/tp invalid")
-            except Exception:
-                raise HTTPException(status_code=400, detail=f"{symbol} 数据库缺少止损/止盈价，且无法回退计算，无法补挂")
+            except Exception as e:
+                raise HTTPException(
+                    status_code=400,
+                    detail=f"{symbol} 无法确定止损止盈价（无 DB 记录且计算失败: {e}），请检查配置 STOP_LOSS_PERCENT/TAKE_PROFIT_PERCENT"
+                )
 
         # 5) 取消旧的保护单（Algo 条件单），避免重复
         try: