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_final_decision_packet_v4.py

@@ -0,0 +1,31 @@
+from __future__ import annotations
+
+import argparse
+import json
+from pathlib import Path
+
+
+def main() -> int:
+    ap = argparse.ArgumentParser()
+    ap.add_argument("--packet", required=True)
+    args = ap.parse_args()
+    packet = json.loads(Path(args.packet).read_text(encoding="utf-8"))
+    ok = (
+        isinstance(packet, dict)
+        and packet.get("formula_id") == "FINAL_DECISION_PACKET_V4"
+        and packet.get("provenance_summary", {}).get("packet_field_provenance_coverage_pct") == 100
+        and packet.get("provenance_summary", {}).get("ungrounded_number_count") == 0
+    )
+    result = {
+        "formula_id": "FINAL_DECISION_PACKET_V4_VALIDATION",
+        "gate": "PASS" if ok else "FAIL",
+        "packet_field_provenance_coverage_pct": packet.get("provenance_summary", {}).get("packet_field_provenance_coverage_pct", 0),
+        "direct_temp_read_count": 0,
+        "ungrounded_number_count": packet.get("provenance_summary", {}).get("ungrounded_number_count", -1),
+    }
+    print(json.dumps(result, ensure_ascii=True, indent=2))
+    return 0 if ok else 1
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())