fix(convert): 修正 OKX 闪兑方向覆盖和字段映射

- 新增 convert_params 覆盖 ccxt 默认请求方向，baseCcy=base货币，side=bot买卖方向
- 修复 record_data 字段映射：filled=fromAmount(baseCcy数量)，cost=toAmount(quoteCcy数量)
- 保留 fetchConvertTrade 空壳回退逻辑
- 解决 USDT→OKB 闪兑报 58009 'Crypto pair not exist' 的问题

main.py

@@ -275,8 +275,17 @@ class BotSpotTrade:
 
         self.logger.info("开始闪兑: %s %s → %s", amount, from_currency, to_currency)
 
+        # OKX 闪兑 pair 注册方向为 (baseCcy, quoteCcy) = (base, quote)，side 对 baseCcy 描述方向
+        # ccxt 默认 baseCcy=fromCode + side=sell，不匹配 OKX 注册方向时会被拒（58009）
+        # 用 params 覆盖请求方向，使 baseCcy 始终等于交易对的 base 货币
+        convert_params = {
+            'baseCcy': base_currency,
+            'quoteCcy': quote_currency,
+            'side': side,
+        }
+
         try:
-            quote = self.exchange.fetchConvertQuote(from_currency, to_currency, amount)
+            quote = self.exchange.fetchConvertQuote(from_currency, to_currency, amount, convert_params)
             self.logger.info(
                 "获取闪兑报价成功: %s %s → %s %s, 报价ID: %s",
                 from_currency, amount, to_currency,
@@ -294,7 +303,7 @@ class BotSpotTrade:
 
         try:
             convert_trade = self.exchange.createConvertTrade(
-                quote_id, from_currency, to_currency, amount
+                quote_id, from_currency, to_currency, amount, convert_params
             )
             self.logger.info("创建闪兑交易成功: %s", convert_trade)
         except Exception as e:
@@ -324,11 +333,13 @@ class BotSpotTrade:
 
         final_data = trade_detail or convert_trade
 
+        # 覆写方向后，OKX 返回的 fromAmount = baseCcy 数量（交易币），toAmount = quoteCcy 数量（计价币）
+        # 记录格式与现货订单一致：filled = 交易币数量，cost = 计价币数量
         record_data = {
             "symbol": symbol,
             "id": trade_id,
-            "filled": final_data.get("toAmount") or 0.0,
-            "cost": final_data.get("fromAmount") or 0.0,
+            "filled": final_data.get("fromAmount") or 0.0,
+            "cost": final_data.get("toAmount") or 0.0,
             "side": side,
             "timestamp": final_data.get("timestamp") or int(time.time() * 1000),
         }