feat: 리밸런싱 엔진 V1 + GAS 버그 수정 (2026-06-13)

주요 변경:
- tools/build_rebalance_engine_v1.py: REBALANCE_ENGINE_V1 신규
  * account_snapshot 직접 합산(_build_snap_position_map) → 소수주 분리 행 병합
  * 레짐 소스 macro.REGIME_PRELIM 최우선 (GAS 와 동일)
- src/gas_adapter_parts/gdf_06_rebalance.gs: runRebalanceSheet_() 신규
  * Logger.log / getSpreadsheet_() 로 run_all 연동 수정
- src/gas_adapter_parts/gdc_01_fetch_fundamentals.gs
  * _mergePositionRecord_(): 소수주 중복 행 합산 신규
  * parseInt → parseFloat (qty, availQty)
- src/gas_adapter_parts/gdf_01_price_metrics.gs
  * 미보유 종목 SELL_READY → WATCH_EXIT_SIGNAL
- spec/41_release_dag.yaml: build_rebalance_sheet 노드 추가 (step_count 63)
- spec/51_formula_lifecycle_registry.yaml: REBALANCE_ENGINE_V1 등록

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tools/validate_imputed_data_exposure_v1.py

@@ -0,0 +1,35 @@
+#!/usr/bin/env python3
+from __future__ import annotations
+
+import argparse
+import json
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[1]
+DEFAULT_JSON = ROOT / "Temp" / "fundamental_raw_evidence_v4.json"
+
+
+def main() -> int:
+    ap = argparse.ArgumentParser()
+    ap.add_argument("--json", default=str(DEFAULT_JSON))
+    args = ap.parse_args()
+    path = Path(args.json)
+    data = json.loads(path.read_text(encoding="utf-8")) if path.exists() else {}
+    exposure = data.get("imputed_data_exposure") if isinstance(data.get("imputed_data_exposure"), dict) else {}
+    has_provenance = bool(data.get("raw_fundamental_value_provenance") is True)
+    has_fields = isinstance(exposure.get("missing_count"), (int, float)) and isinstance(exposure.get("coverage_pct"), (int, float))
+    ok = has_provenance and has_fields
+    payload = {
+        "formula_id": "IMPUTED_DATA_EXPOSURE_V1",
+        "gate": "PASS" if ok else "FAIL",
+        "missing_count": int(exposure.get("missing_count") or 0),
+        "coverage_pct": float(exposure.get("coverage_pct") or 0.0),
+        "has_provenance": has_provenance,
+    }
+    print(json.dumps(payload, ensure_ascii=True, indent=2))
+    return 0 if ok else 1
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())