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>

runtime/refactor_baseline_v_next.yaml

@@ -0,0 +1,19 @@
+{
+  "formula_id": "AUDIT_REPOSITORY_ENTROPY_V2",
+  "gate": "PASS",
+  "total_file_count": 1514,
+  "package_script_count": 22,
+  "temp_json_count": 53,
+  "budget": {
+    "schema_version": "repository_entropy_budget.v1",
+    "max_total_files": 2000,
+    "max_package_scripts": 220,
+    "max_temp_json_files": 500,
+    "max_docs_lines": 120000,
+    "release_budget_notes": [
+      "archive stale Temp JSONs when safe",
+      "keep package scripts within release envelope"
+    ]
+  },
+  "source_zip_sha256": "1b05800cfe967f949d2aa83d508064fb005995a42fe1e81722e8fb79d3f7cae9"
+}