feat: report bootstrap confidence intervals

tests/test_backtest_statistics.py

@@ -1,4 +1,4 @@
-from backtesting import statistics
+from backtesting import engine, statistics
 
 
 def test_moving_block_bootstrap_is_deterministic_and_handles_constant_series():
@@ -32,3 +32,14 @@ def test_summarize_returns_reports_observations_and_block_bootstrap_interval():
     assert summary["median"] == 2.5
     assert summary["win_rate"] == 50.0
     assert summary["mean_ci_low"] <= summary["mean"] <= summary["mean_ci_high"]
+
+
+def test_backtest_brackets_publish_bootstrap_confidence_intervals():
+    stats = {}
+
+    engine._add_return_statistics(stats, "90d", [10.0, -5.0, 20.0, -10.0])
+
+    assert stats["avg_90d"] == 3.75
+    assert stats["median_90d"] == 2.5
+    assert stats["win_rate_90d"] == 50.0
+    assert stats["avg_90d_ci_low"] <= stats["avg_90d"] <= stats["avg_90d_ci_high"]