style: format Go code with go fmt

- Fix formatting issues flagged by PR advisory checks
- Run go fmt ./... on all Go files
- No functional changes, code style improvements only

Files formatted:
- api/server.go
- auth/auth.go
- decision/engine.go
- logger/decision_logger.go
- manager/trader_manager.go
- market/monitor.go
- market/types.go
- mcp/client.go
- trader/*.go (aster, auto, binance, hyperliquid)

trader/hyperliquid_trader.go

@@ -17,7 +17,7 @@ type HyperliquidTrader struct {
 	ctx           context.Context
 	walletAddr    string
 	meta          *hyperliquid.Meta // 缓存meta信息（包含精度等）
-	isCrossMargin bool             // 是否为全仓模式
+	isCrossMargin bool              // 是否为全仓模式
 }
 
 // NewHyperliquidTrader 创建Hyperliquid交易器