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/build_artifact_chain_hash_v4.py

@@ -0,0 +1,54 @@
+#!/usr/bin/env python3
+import json
+import hashlib
+from pathlib import Path
+from datetime import datetime, timezone
+
+ROOT = Path(__file__).resolve().parents[1]
+
+def file_sha256(path: Path) -> str:
+    if not path.exists():
+        return ""
+    h = hashlib.sha256()
+    with path.open("rb") as f:
+        for chunk in iter(lambda: f.read(65536), b""):
+            h.update(chunk)
+    return h.hexdigest()
+
+def main():
+    chain_paths = [
+        "GatherTradingData.json",
+        "Temp/final_decision_packet_active.json",
+        "Temp/number_provenance_ledger_v4.json",
+        "Temp/operational_report.json"
+    ]
+    
+    chain = []
+    parent_hash = "0" * 64
+    
+    for p in chain_paths:
+        path = ROOT / p
+        h = file_sha256(path)
+        
+        node = {
+            "path": p,
+            "sha256": h,
+            "generated_at": datetime.fromtimestamp(path.stat().st_mtime, tz=timezone.utc).isoformat() if path.exists() else None,
+            "parent_hash": parent_hash
+        }
+        chain.append(node)
+        parent_hash = h
+
+    result = {
+        "formula_id": "ARTIFACT_CHAIN_HASH_V4",
+        "chain": chain,
+        "chain_length": len([c for c in chain if c["sha256"]])
+    }
+    
+    out_path = ROOT / "Temp" / "artifact_chain_hash_v4.json"
+    out_path.write_text(json.dumps(result, indent=2, ensure_ascii=False), encoding="utf-8")
+    print(f"Chain built: {len(chain)} artifacts tracked.")
+    return 0
+
+if __name__ == "__main__":
+    main()