feat: Enhance Optuna integration and logging for backtesting framework

Changes:
- Added new API endpoints for continuing and confirming Optuna jobs, allowing for better management of ongoing studies.
- Introduced detailed logging for tick feed tracking and order book processing, improving traceability of vendor performance during backtests.
- Updated database schema to include new fields for managing Optuna study results, enhancing the ability to track study progress and outcomes.
- Refactored existing functions to utilize the new logging and tracking features, ensuring consistency across the backtesting framework.

Impact:
- These enhancements improve the robustness and transparency of the Optuna backtesting process, facilitating better analysis and optimization of trading strategies.

kis_trader/engine/live_sell_price.py

@@ -18,6 +18,31 @@ from kis_trader.utils.env import get_env_float
 _stale_rest_lock = threading.Lock()
 _stale_rest_ts: dict = {}
 _stale_log_ts: dict = {}
+# WS/REST 성공 직후 가격 — REST 쿨다운(기본 30s) 동안 재사용 (매도 공백 방지)
+_last_good_lock = threading.Lock()
+_last_good_px: dict = {}
+
+
+def _remember_last_good(code: str, px: float, src: str) -> None:
+    code = str(code or "").strip()
+    if not code or px <= 0:
+        return
+    with _last_good_lock:
+        _last_good_px[code] = (float(px), str(src or "WS"), time.time())
+
+
+def _last_good_price(code: str, max_age_sec: float) -> Tuple[float, str]:
+    code = str(code or "").strip()
+    if not code or max_age_sec <= 0:
+        return 0.0, ""
+    with _last_good_lock:
+        rec = _last_good_px.get(code)
+    if not rec:
+        return 0.0, ""
+    px, src, ts = rec
+    if (time.time() - float(ts)) > float(max_age_sec):
+        return 0.0, ""
+    return float(px), str(src or "")
 
 
 def _stck_prpr(raw: Any) -> float:
@@ -63,6 +88,43 @@ def _ws_chain_price(ws: Any, code: str) -> Tuple[float, str]:
     return 0.0, ""
 
 
+def _quote_packet_raw(wsd: Any) -> str:
+    """체결시각 원문. FID20 동결 RAM 을 매도 last-RAM 으로 쓰지 않기 위함."""
+    if not isinstance(wsd, dict):
+        return ""
+    for k in (
+        "kis_cntg_hour_raw", "chetime", "tick_time", "kiwoom_fid20",
+        "stck_cntg_hour",
+    ):
+        v = str(wsd.get(k) or "").strip()
+        if v:
+            return v
+    return ""
+
+
+def _last_ram_sell_ok(wsd: Any, max_age_sec: float) -> bool:
+    """마지막 RAM: wall 나이·패킷 나이 둘 다 max 이내. 동결 FID20 거부."""
+    if max_age_sec <= 0 or not isinstance(wsd, dict):
+        return False
+    try:
+        wall = float(wsd.get("_age_ms") or 0) / 1000.0
+    except (TypeError, ValueError):
+        wall = 0.0
+    if wall > float(max_age_sec):
+        return False
+    raw = _quote_packet_raw(wsd)
+    if not raw:
+        return True
+    try:
+        from kis_trader.engine.feed_fallback import packet_lag_seconds
+        lag = packet_lag_seconds(raw)
+    except Exception:
+        return True
+    if lag is None:
+        return True
+    return float(lag) <= float(max_age_sec)
+
+
 def _ws_last_and_age(ws: Any, code: str) -> Tuple[float, float]:
     """마지막 RAM 체결가 + 나이(초). 캐시 없으면 (0, inf). EOD 전용."""
     getter = getattr(ws, "get_price", None)
@@ -153,6 +215,7 @@ def resolve_live_sell_price(
     if is_eod:
         ws_px, _age = _ws_last_and_age(ws, code)
         if ws_px > 0:
+            _remember_last_good(code, ws_px, "WS")
             return ws_px, "WS"
         if stale_sec > 0 and _stale_rest_allowed(code, cooldown):
             rest_px = _kiwoom_rest_once(ws, code)
@@ -171,11 +234,52 @@ def resolve_live_sell_price(
 
     chain_px, vendor = _ws_chain_price(ws, code)
     if chain_px > 0:
+        _remember_last_good(code, chain_px, vendor or "WS")
         return chain_px, vendor or "WS"
 
+    last_max = float(get_env_float("SELL_WS_LAST_RAM_MAX_AGE_SEC", 30.0) or 0.0)
+    if last_max > 0:
+        last_px, last_age = _ws_last_and_age(ws, code)
+        getter = getattr(ws, "get_price", None)
+        wsd_last = None
+        if callable(getter):
+            try:
+                wsd_last = getter(code, max_age_sec=None)
+            except TypeError:
+                wsd_last = None
+            except Exception:
+                wsd_last = None
+        if last_px > 0 and _last_ram_sell_ok(wsd_last, last_max):
+            lab = ""
+            if isinstance(wsd_last, dict):
+                lab = str(wsd_last.get("_feed_vendor") or "").strip()
+            _remember_last_good(code, last_px, lab or "WS_last")
+            _log_throttled(
+                logger,
+                "last_ram:" + code,
+                "📌 [매도시세] %s 3초체인 실패 → last-RAM %.0f (age=%.1fs)",
+                code,
+                last_px,
+                last_age if last_age != float("inf") else -1.0,
+            )
+            return last_px, "WS_last"
+
+    cached_px, cached_src = _last_good_price(code, cooldown)
+    if cached_px > 0:
+        _log_throttled(
+            logger,
+            "last_good:" + code,
+            "📌 [매도시세] %s WS체인 실패 → 직전가 유지(%s) %.0f",
+            code,
+            cached_src,
+            cached_px,
+        )
+        return cached_px, cached_src + "_cached"
+
     if stale_sec > 0 and _stale_rest_allowed(code, cooldown):
         rest_px = _kiwoom_rest_once(ws, code)
         if rest_px > 0:
+            _remember_last_good(code, rest_px, "kiwoom_rest")
             _log_throttled(
                 logger,
                 "stale_rest:" + code,