Add metrics for xgboost (USD_JPY H1)

models/xgboost/USD_JPY_H1/metrics.json

@@ -0,0 +1,15 @@
+{
+  "accuracy": 0.2617975117975118,
+  "f1_weighted": 0.28365229002639153,
+  "precision": 0.6505737681167574,
+  "recall": 0.2617975117975118,
+  "initial_capital": 10000.0,
+  "final_equity": 10000.0,
+  "total_return_pct": 0.0,
+  "max_drawdown_pct": 0.0,
+  "sharpe_ratio": 0.0,
+  "total_trades": 0,
+  "win_rate_pct": 0.0,
+  "avg_pnl_per_trade": 0.0,
+  "trades_per_1000_bars": 0.0
+}