feat: Enhance trading system with new e_min_chg_pct parameter and related logic

Changes:
- Introduced the `e_min_chg_pct` parameter to define the minimum price change percentage compared to the previous day's close, enhancing the momentum trading strategy.
- Updated various functions and classes to incorporate this new parameter, ensuring it is utilized in both backtesting and live trading scenarios.
- Improved documentation and comments to clarify the purpose and usage of the new parameter across the codebase.

Impact:
- This addition allows for more precise control over trading conditions, potentially increasing the effectiveness of the momentum strategy while maintaining system integrity and performance.

kis_trader/backtest/scalping_backtest_common.py

@@ -157,7 +157,11 @@ def load_scalp_candles_by_code(
     *,
     history_source: str = "kiwoom",
 ) -> Tuple[Dict[str, List[Dict]], int]:
-    """1분봉 전 종목 로드 (+ 웜업). history_source=ls → ls_ws_candles."""
+    """1분봉 전 종목 로드 (+ 웜업). history_source=ls → ls_ws_candles.
+
+    반환은 ``(candles_by_code, total_rows)`` 만 — 호출부에 ``codes`` 리스트 없음.
+    웹 ``codes_analyzed`` 는 ``_codes_from_candles_map`` 으로 바인딩할 것.
+    """
     min_bars = int(rsi_period) + 5
     hs = str(history_source or "kiwoom").strip().lower()
     if hs in ("ls", "ls_condition", "ls_ws"):