feat: add xyz dex balance calculation, market data providers, and UI improvements

- Fix xyz dex balance calculation (use marginSummary for isolated margin)
- Add Alpaca provider for US stocks market data
- Add TwelveData provider for forex & metals market data
- Add Hyperliquid kline provider
- Centralize API keys in config system
- Add builder fee for order routing
- Improve chart UI with compact design
- Fix position history fee display precision
- Add comprehensive balance calculation tests

provider/alpaca/kline_test.go

@@ -0,0 +1,35 @@
+package alpaca
+
+import (
+	"context"
+	"fmt"
+	"testing"
+)
+
+func TestGetBars(t *testing.T) {
+	client := NewClient()
+
+	resp, err := client.GetBars(context.TODO(), "AAPL", "1Day", 5)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Log("=== AAPL 日线数据 (Alpaca IEX feed) ===")
+	for i, bar := range resp {
+		t.Logf("\n[%d] 时间: %s", i, bar.Timestamp.Format("2006-01-02 15:04:05"))
+		t.Logf("    Open:       %.2f", bar.Open)
+		t.Logf("    High:       %.2f", bar.High)
+		t.Logf("    Low:        %.2f", bar.Low)
+		t.Logf("    Close:      %.2f", bar.Close)
+		t.Logf("    Volume:     %d (股数)", bar.Volume)
+		t.Logf("    TradeCount: %d (成交笔数)", bar.TradeCount)
+		t.Logf("    VWAP:       %.2f (成交量加权平均价)", bar.VWAP)
+
+		// 计算成交额
+		quoteVolume := float64(bar.Volume) * bar.Close
+		t.Logf("    成交额:     %.2f USD (Volume × Close)", quoteVolume)
+	}
+
+	fmt.Printf("\n⚠️ 注意：IEX feed 只包含 IEX 交易所的数据，不是完整市场数据\n")
+	fmt.Printf("完整市场数据需要使用 SIP feed（付费）\n")
+}