feat(safety-sell): dcy-007 core 자율 안전 매도 — BAT-010 기반 + BAT-011 트리거

dcy-007(core 자율 안전 매도) 전체 delivery. BAT-010 기반 인프라가 미커밋
상태였고 BAT-011 트리거 레이어와 공유 파일에서 섞여 있어 한 커밋으로 묶음.

BAT-010 (REQ-034/035/036/041, release-candidate):
- WatchdogStore(application/watchdog.py) + snapshot RPC 워치독 갱신
- Slot stop_loss_price/take_profit_price 필드 + 004_add_price_thresholds.sql
- SlotService.sell() 자율 매도 내부 경로 + idempotency
- SafetySellConfig env 5종 파싱

BAT-011 (REQ-037/038/039/040/042, release-candidate):
- SafetySellService(application/safety_sell.py): forced_close 만기 / stop-loss·
  take-profit KIS polling / 장 마감 강제 청산 + trex-safety-sell 7번째 스레드
- BrokerPort.get_current_price + KIS inquire-price(TTTC8397R/VTTC8397R, stck_prpr)
  + paper stub
- SlotService.update_thresholds() + intent RPC update_thresholds 액션
  (부분 갱신/null 해제, 워치독 last_seen_at 리셋)
- baseline 3문서 정합(interface-contract/runtime-flows/project-structure)

거버넌스: REQ-034~042 Implemented 동기화, BAT-010/011 release-candidate,
dcy-007 discovery 포함.

검증: 신규 38 테스트 green, 단위 236 passed/23 skipped,
인프라 게이트(PG+RabbitMQ) 259 passed(마이그레이션 001~004 round-trip 포함),
ruff clean.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/runtime/test_safety_sell_config.py

@@ -0,0 +1,69 @@
+"""SafetySellConfig env-var parsing tests (REQ-041 / BAT-010)."""
+from __future__ import annotations
+
+import pytest
+
+from trex_core.runtime.config import DaemonConfig, SafetySellConfig
+
+_SAFETY_KEYS = (
+    "TREX_WATCHDOG_TIMEOUT",
+    "TREX_WATCHDOG_GRACE_PERIOD",
+    "TREX_FORCED_CLOSE_CHECK_INTERVAL",
+    "TREX_STOP_LOSS_POLL_INTERVAL",
+    "TREX_MARKET_CLOSE_LIQUIDATION_TIME",
+)
+
+
+@pytest.fixture(autouse=True)
+def _clean_env(monkeypatch):
+    for k in _SAFETY_KEYS:
+        monkeypatch.delenv(k, raising=False)
+
+
+@pytest.fixture
+def _base_env(monkeypatch):
+    monkeypatch.setenv("TREX_POSTGRESQL_DSN", "dbname=x")
+
+
+def test_safety_sell_config_defaults(tmp_path, monkeypatch, _base_env):
+    """AC-1: unset env vars produce documented defaults."""
+    monkeypatch.chdir(tmp_path)
+    cfg = DaemonConfig.from_env()
+    ss = cfg.safety_sell
+    assert ss.watchdog_timeout_sec == 120
+    assert ss.watchdog_grace_period_sec == 60
+    assert ss.forced_close_check_interval_sec == 60
+    assert ss.stop_loss_poll_interval_sec == 30
+    assert ss.market_close_liquidation_time is None
+
+
+def test_safety_sell_config_env_tuning(tmp_path, monkeypatch, _base_env):
+    """AC-2~5: all five env vars are parsed correctly."""
+    monkeypatch.chdir(tmp_path)
+    monkeypatch.setenv("TREX_WATCHDOG_TIMEOUT", "180")
+    monkeypatch.setenv("TREX_WATCHDOG_GRACE_PERIOD", "90")
+    monkeypatch.setenv("TREX_FORCED_CLOSE_CHECK_INTERVAL", "45")
+    monkeypatch.setenv("TREX_STOP_LOSS_POLL_INTERVAL", "15")
+    monkeypatch.setenv("TREX_MARKET_CLOSE_LIQUIDATION_TIME", "15:30")
+    cfg = DaemonConfig.from_env()
+    ss = cfg.safety_sell
+    assert ss.watchdog_timeout_sec == 180
+    assert ss.watchdog_grace_period_sec == 90
+    assert ss.forced_close_check_interval_sec == 45
+    assert ss.stop_loss_poll_interval_sec == 15
+    assert ss.market_close_liquidation_time == "15:30"
+
+
+def test_market_close_liquidation_time_empty_string_becomes_none(tmp_path, monkeypatch, _base_env):
+    """Empty string for optional field collapses to None."""
+    monkeypatch.chdir(tmp_path)
+    monkeypatch.setenv("TREX_MARKET_CLOSE_LIQUIDATION_TIME", "")
+    cfg = DaemonConfig.from_env()
+    assert cfg.safety_sell.market_close_liquidation_time is None
+
+
+def test_safety_sell_config_is_frozen():
+    """SafetySellConfig is a frozen dataclass."""
+    ss = SafetySellConfig()
+    with pytest.raises((AttributeError, TypeError)):
+        ss.watchdog_timeout_sec = 999  # type: ignore[misc]