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_agents_shrink_v1.py

@@ -0,0 +1,43 @@
+"""validate_agents_shrink_v1.py — AGENTS shrink validator"""
+from __future__ import annotations
+
+import hashlib
+from pathlib import Path
+
+import yaml
+
+
+ROOT = Path(__file__).resolve().parents[1]
+AGENTS = ROOT / "AGENTS.md"
+INDEX = ROOT / "governance" / "agents_index.yaml"
+
+
+def _sha256(path: Path) -> str:
+    return hashlib.sha256(path.read_bytes()).hexdigest()
+
+
+def main() -> int:
+    lines = AGENTS.read_text(encoding="utf-8").splitlines()
+    if len(lines) > 350:
+        print(f"AGENTS_SHRINK_FAIL: AGENTS.md lines={len(lines)} > 350")
+        return 1
+    if not INDEX.exists():
+        print("AGENTS_SHRINK_FAIL: missing governance/agents_index.yaml")
+        return 1
+    index = yaml.safe_load(INDEX.read_text(encoding="utf-8")) or {}
+    rule_files = index.get("rule_files") if isinstance(index.get("rule_files"), list) else []
+    missing = []
+    for rel in rule_files:
+        path = ROOT / str(rel)
+        if not path.exists():
+            missing.append(str(rel))
+    if missing:
+        print(f"AGENTS_SHRINK_FAIL: missing rule files {missing}")
+        return 1
+    print("AGENTS_SHRINK_OK")
+    print(f"agents_lines={len(lines)} rule_files={len(rule_files)}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())