fix: DB 타임스탬프 KST 통일 + KIS 토큰 캐시 영속화

시간대 혼재: 모델 기본값은 datetime.utcnow(UTC), 수동 매매 등 일부 경로는 _get_kst_now(KST)로
저장해 같은 테이블에 9시간 차가 섞였다(화면 매매시각 02:14 등). 조회 구간(utcnow - days)도
KST 저장분과 비교돼 어긋났고, 추가매수 쿨다운은 (UTC now - KST created_at)이 음수라 상시
발동했다. app.core.timeutil.now_kst() 도입 후 모델 기본값 27곳과 app/ 전역 utcnow() 호출을
모두 KST 기준으로 통일(잔존 0건, 테스트로 고정).

KIS 토큰 캐시(~/.cache/auto-stock)가 컨테이너에만 있어 배포마다 사라지고 토큰을 새로
발급받다 KIS가 EGW00103(유효하지 않은 AppKey)로 거부 → 502·잔고 0 유발. 볼륨 마운트로
재배포 후에도 재사용.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

backend/app/api/endpoints/analysis.py

@@ -18,6 +18,7 @@ from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.core.database import get_db, AsyncSessionLocal
 from app.models.models import StrategyOptimizationLog, TradeJournal
+from app.core.timeutil import now_kst
 from app.services.trade_analyzer import (
     analyze_performance,
     build_insights,
@@ -71,7 +72,7 @@ async def get_insights(
             "performance_summary": perf.get("summary", {}),
             "last_optimization_date": last_opt_date.isoformat() if last_opt_date else None,
             "period_days": days,
-            "generated_at": datetime.utcnow().isoformat(),
+            "generated_at": now_kst().isoformat(),
         }
     except Exception as e:
         logger.error(f"insights 생성 실패: {e}", exc_info=True)

backend/app/api/endpoints/auth.py

@@ -42,6 +42,7 @@ from app.core.security import (
     verify_session_token,
 )
 from app.models.models import User
+from app.core.timeutil import now_kst
 
 logger = logging.getLogger(__name__)
 router = APIRouter()
@@ -246,7 +247,7 @@ async def login(body: LoginRequest, request: Request, db: AsyncSession = Depends
         )
 
     _failures.pop(ip, None)
-    user.last_login_at = datetime.utcnow()
+    user.last_login_at = now_kst()
     await db.commit()
 
     token, expires_at = create_session_token(user.username)

backend/app/api/endpoints/kis_credentials.py

@@ -27,6 +27,7 @@ from app.core.tenant_auth import CurrentUser, get_current_user
 from app.models.models import UserKisCredential
 from app.services.korea_investment_api import KoreaInvestmentAPI
 from app.services.tenant.registry import user_context_registry
+from app.core.timeutil import now_kst
 
 logger = logging.getLogger(__name__)
 router = APIRouter()
@@ -172,7 +173,7 @@ async def put_credentials(
     if dup.scalar_one_or_none() is not None:
         raise HTTPException(status_code=status.HTTP_409_CONFLICT, detail="이미 다른 사용자가 등록한 앱키입니다.")
 
-    now = datetime.utcnow()
+    now = now_kst()
     cred = await _get_own(db, user_id)
     is_new = cred is None
     if is_new:
@@ -278,7 +279,7 @@ async def verify_credentials(
         "stock_value": _pick_float(output2, ["scts_evlu_amt", "evlu_amt_smtl_amt"]),
     }
 
-    now = datetime.utcnow()
+    now = now_kst()
     cred.last_verified_at = now
     cred.is_enabled = True
     cred.updated_at = now
@@ -306,7 +307,7 @@ async def patch_auto_trade(
         )
 
     cred.auto_trade_enabled = body.enabled
-    cred.updated_at = datetime.utcnow()
+    cred.updated_at = now_kst()
     await db.commit()
     # H3: 캐시된 UserContext.auto_trade_enabled 스냅샷이 갱신되도록 무효화(다음 호출에서 재조립).
     await user_context_registry.invalidate(user_id)

backend/app/api/endpoints/portfolio.py

@@ -29,6 +29,7 @@ from app.services.utils import _is_domestic
 import asyncio
 import logging
 from datetime import datetime, timedelta
+from app.core.timeutil import now_kst
 
 logger = logging.getLogger(__name__)
 
@@ -1428,7 +1429,7 @@ async def _create_journal_background(
             "trade_id": trade_id,
             "stock_code": stock_code,
             "stock_name": stock_name,
-            "journal_date": datetime.utcnow(),
+            "journal_date": now_kst(),
             "content": content,
             "strategy_name": "AUTO_TRADE",
             "mood": mood,
@@ -1699,7 +1700,7 @@ async def update_active_trade_status(
 
         # 상태 업데이트
         active_trade.status = new_status
-        active_trade.updated_at = datetime.fromisoformat(request.updated_at) if request.updated_at else datetime.utcnow()
+        active_trade.updated_at = datetime.fromisoformat(request.updated_at) if request.updated_at else now_kst()
 
         # 부분 매도 시 잔여 비율 갱신 (CLAUDE.md 5.2: +2R 50% 분할 매도 후 잔량 추적 유지)
         if request.remaining_pct is not None:

backend/app/api/endpoints/risk_management.py

@@ -28,6 +28,7 @@ def _today_kst() -> date:
 from app.core.config import settings
 from app.core.security import require_api_key
 from app.models.models import TradeHistory, TradingSession, Portfolio
+from app.core.timeutil import now_kst
 
 router = APIRouter()
 logger = logging.getLogger(__name__)
@@ -54,7 +55,7 @@ async def get_risk_metrics(
     - 현재 계좌 상태
     """
     try:
-        since_date = datetime.utcnow() - timedelta(days=days)
+        since_date = now_kst() - timedelta(days=days)
         
         # 매도 완료된 거래만 조회 (실현 손익)
         result = await db.execute(
@@ -149,7 +150,7 @@ async def get_sharpe_ratio(
     - < 1.0: 개선 필요
     """
     try:
-        since_date = datetime.utcnow() - timedelta(days=days)
+        since_date = now_kst() - timedelta(days=days)
         
         result = await db.execute(
             select(TradeHistory)
@@ -443,7 +444,7 @@ async def get_win_rate(
     📊 승률 및 손익 통계
     """
     try:
-        since_date = datetime.utcnow() - timedelta(days=days)
+        since_date = now_kst() - timedelta(days=days)
         
         result = await db.execute(
             select(TradeHistory)

backend/app/api/endpoints/trades.py

@@ -17,6 +17,7 @@ import re
 from app.core.database import get_db
 from app.models.models import TradeHistory
 from pydantic import BaseModel
+from app.core.timeutil import now_kst
 
 router = APIRouter()
 logger = logging.getLogger(__name__)
@@ -62,7 +63,7 @@ async def get_trade_history(
     query = select(TradeHistory)
     
     # 날짜 필터
-    since_date = datetime.utcnow() - timedelta(days=days)
+    since_date = now_kst() - timedelta(days=days)
     query = query.where(TradeHistory.created_at >= since_date)
     
     # 종목 코드 필터
@@ -158,7 +159,7 @@ async def get_trade_stats(
     db: AsyncSession = Depends(get_db)
 ):
     """거래 통계 조회"""
-    since_date = datetime.utcnow() - timedelta(days=days)
+    since_date = now_kst() - timedelta(days=days)
     
     result = await db.execute(
         select(TradeHistory).where(TradeHistory.created_at >= since_date)

backend/app/api/endpoints/trades_v2.py

@@ -22,6 +22,7 @@ from app.core.tenant_auth import CurrentUser, get_current_user
 from app.models.models import TradeHistory
 from app.api.endpoints.portfolio_v2 import _resolve_target_user_id, _user_scope_filter
 from app.api.endpoints.trades import TradeHistoryResponse
+from app.core.timeutil import now_kst
 
 logger = logging.getLogger(__name__)
 router = APIRouter()
@@ -44,7 +45,7 @@ async def get_trade_history_v2(
 
     query = select(TradeHistory).where(_user_scope_filter(TradeHistory.user_id, target_user_id))
 
-    since_date = datetime.utcnow() - timedelta(days=days)
+    since_date = now_kst() - timedelta(days=days)
     query = query.where(TradeHistory.created_at >= since_date)
 
     if stock_code:

backend/app/api/endpoints/trading_rules.py

@@ -18,6 +18,7 @@ from app.core.database import get_db
 from app.core.security import require_api_key
 from app.models.models import TradingRule
 from pydantic import BaseModel
+from app.core.timeutil import now_kst
 
 router = APIRouter()
 
@@ -118,7 +119,7 @@ async def update_trading_rule(
     for field, value in update_data.items():
         setattr(db_rule, field, value)
     
-    db_rule.updated_at = datetime.utcnow()
+    db_rule.updated_at = now_kst()
     await db.commit()
     await db.refresh(db_rule)
     return db_rule
@@ -148,7 +149,7 @@ async def toggle_trading_rule(rule_id: int, db: AsyncSession = Depends(get_db)):
         raise HTTPException(status_code=404, detail="Trading rule not found")
     
     db_rule.is_active = not db_rule.is_active
-    db_rule.updated_at = datetime.utcnow()
+    db_rule.updated_at = now_kst()
     await db.commit()
     await db.refresh(db_rule)
     return db_rule