fix: 删除零成交误判逻辑 + 各种稳定性修复

- 删除: Bitget GetTradeFee 零成交检查（PlaceMarketOrder 成功即成交）
- 修复: GetTradeFee 加 1s 延迟 + 查不到返回 0（用配置估算费兜底）
- 修复: HL InitExchange 在 NewTrader 中提前调用，避免 szDecimals 延迟
- 修复: close_failed 30 次重试上限，超限标记 failed 并清理
- 修复: DB 恢复时校验 Legs 完整性，跳过非法记录
- 修复: checkScaleIn/checkExit nil guard 防 panic
- 修复: config.go 参数调整（手续费、阈值等）
- 移除: scanner.go 中 MEW/USTC 等低流动性币对
- 添加: 更详细的下单日志（szStr、amountUSD、price）
- 添加: bin/ 到 .gitignore

exchange/bitget_trade.go

@@ -81,9 +81,12 @@ func (b *BitgetTrade) PlaceMarketOrder(side, symbol, size, tradeSide string) (st
 	}
 	return result.Data.OrderID, nil
 }
-
 // GetTradeFee queries the fills endpoint for actual fee charged.
+// Waits 1s before querying because Bitget's fills API may lag behind
+// the place-order response. Returns 0 if no fills yet (caller uses
+// estimated fee from config as fallback).
 func (b *BitgetTrade) GetTradeFee(symbol, orderID string) (feeUSD float64, err error) {
+	time.Sleep(1 * time.Second)
 	ts := fmt.Sprintf("%d", time.Now().UnixMilli())
 	method := "GET"
 	requestPath := "/api/v2/mix/order/fills?symbol=" + symbol + "&orderId=" + orderID + "&productType=USDT-FUTURES"
@@ -92,6 +95,7 @@ func (b *BitgetTrade) GetTradeFee(symbol, orderID string) (feeUSD float64, err e
 	sign := b.sign(method, requestPath, ts, "")
 	url := host + requestPath
 	req, _ := http.NewRequest(method, url, nil)
+	req.Header.Set("Content-Type", "application/json")
 	req.Header.Set("ACCESS-KEY", b.APIKey)
 	req.Header.Set("ACCESS-SIGN", sign)
 	req.Header.Set("ACCESS-TIMESTAMP", ts)
@@ -121,7 +125,7 @@ func (b *BitgetTrade) GetTradeFee(symbol, orderID string) (feeUSD float64, err e
 	var totalFee float64
 	for _, item := range raw.Data.FillList {
 		var fill struct {
-			FillFee string `json:"fillFee"`
+			FillFee  string `json:"fillFee"`
 		}
 		if err := json.Unmarshal(item, &fill); err != nil {
 			continue