baseline: byte-for-byte backtest reference at da61cff + compare tooling

Pin reference outputs of backtest/gpu_backtest.py (XAU/USD, window
2025-08-04..2026-08-04, 4 primary TFs x spread 0.30/0.65 = 8 runs) under
baseline/da61cff/: trade books, stdout summaries, derived equity curves
and metrics, plus a manifest with exact argv, input-parquet and output
hashes, backend, and tool versions.

scripts/capture_baseline.py captures (cache-warm only, aborts rather
than fetch live); scripts/compare_baseline.py re-runs the identical
commands and byte-diffs every output, PASS/FAIL per file. Verified
32/32 files PASS on full re-run at this commit; m5_s065 reproduces the
pinned HEAD reference exactly (555 trades, +98.64R, PF 1.483). No
signal, execution, or scanner logic touched; 359 tests green.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01J3mZCQRHnJKt7qXQFG3RhB

baseline/da61cff/h4_s030/metrics.json

@@ -0,0 +1,48 @@
+{
+  "by_quality": {
+    "A": {
+      "max_dd_r": -4.036504,
+      "profit_factor": 1.908268,
+      "total_r": 6.491869,
+      "trades": 19,
+      "win_rate_pct": 57.894737
+    },
+    "A+": {
+      "max_dd_r": -1.09013,
+      "profit_factor": 2.186641,
+      "total_r": 1.293592,
+      "trades": 5,
+      "win_rate_pct": 60.0
+    },
+    "B": {
+      "max_dd_r": -2.001012,
+      "profit_factor": 3.854359,
+      "total_r": 9.542664,
+      "trades": 17,
+      "win_rate_pct": 70.588235
+    },
+    "C": {
+      "max_dd_r": -1.003833,
+      "profit_factor": 0.0,
+      "total_r": -1.003833,
+      "trades": 1,
+      "win_rate_pct": 0.0
+    }
+  },
+  "by_strategy": {
+    "GENERIC": {
+      "max_dd_r": -3.546541,
+      "profit_factor": 2.297156,
+      "total_r": 16.324293,
+      "trades": 42,
+      "win_rate_pct": 61.904762
+    }
+  },
+  "overall": {
+    "max_dd_r": -3.546541,
+    "profit_factor": 2.297156,
+    "total_r": 16.324293,
+    "trades": 42,
+    "win_rate_pct": 61.904762
+  }
+}