feat: add trade_id + full trade record to trade_results

Each buy generates a UUID trade_id stored in positions table.
Each sell links via same trade_id in trade_results, enabling
round-trip grouping of buy→sell pairs.

Additional fields saved per trade:
- fee_krw: commission amount (0.05% each side)
- krw_profit: net KRW profit/loss after fees
- buy_price / sell_price: exact prices
- invested_krw: capital deployed
- sell_reason: trailing stop / time stop / etc.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

core/trader.py

@@ -6,6 +6,7 @@ import logging
 import os
 import threading
 import time
+import uuid
 from datetime import datetime
 from typing import Optional
 
@@ -60,7 +61,13 @@ def _get_history(ticker: str) -> list[bool]:
     return _trade_history[ticker]
 
 
-def _update_history(ticker: str, is_win: bool, pnl_pct: float) -> None:
+def _update_history(
+    ticker: str, is_win: bool, pnl_pct: float,
+    fee_krw: float = 0.0, krw_profit: float = 0.0,
+    trade_id: str = "", buy_price: float = 0.0,
+    sell_price: float = 0.0, invested_krw: int = 0,
+    sell_reason: str = "",
+) -> None:
     """매도 후 in-memory 이력 갱신 + DB 기록."""
     hist = _trade_history.setdefault(ticker, [])
     hist.append(is_win)
@@ -68,7 +75,10 @@ def _update_history(ticker: str, is_win: bool, pnl_pct: float) -> None:
     if len(hist) > WF_WINDOW * 2:
         _trade_history[ticker] = hist[-WF_WINDOW:]
     try:
-        record_trade(ticker, is_win, pnl_pct)
+        record_trade(
+            ticker, is_win, pnl_pct, fee_krw, krw_profit,
+            trade_id, buy_price, sell_price, invested_krw, sell_reason,
+        )
     except Exception as e:
         logger.error(f"거래 이력 저장 실패 {ticker}: {e}")
 
@@ -83,6 +93,7 @@ def _db_upsert(ticker: str, pos: dict) -> None:
             amount=pos["amount"],
             invested_krw=pos["invested_krw"],
             entry_time=pos["entry_time"].isoformat(),
+            trade_id=pos.get("trade_id", ""),
         )
     except Exception as e:
         logger.error(f"포지션 DB 저장 실패 {ticker}: {e}")
@@ -158,6 +169,7 @@ def restore_positions() -> None:
                     "amount": amount,
                     "invested_krw": s["invested_krw"],
                     "entry_time": entry_time,
+                    "trade_id": s.get("trade_id", ""),
                 }
             logger.info(
                 f"[복원] {ticker} 매수가={s['buy_price']:,.0f}원 | 현재가={current:,.0f}원 "
@@ -252,17 +264,19 @@ def buy(ticker: str) -> bool:
             actual_price = order_krw / amount if amount > 0 else pyupbit.get_current_price(ticker)
 
             entry_time = datetime.now()
+            trade_id = str(uuid.uuid4())
             _positions[ticker] = {
                 "buy_price": actual_price,
                 "peak_price": actual_price,
                 "amount": amount,
                 "invested_krw": order_krw,
                 "entry_time": entry_time,
+                "trade_id": trade_id,
             }
             _db_upsert(ticker, _positions[ticker])
             logger.info(
                 f"[매수] {ticker} @ {actual_price:,.0f}원 (실체결가) | "
-                f"수량={amount} | 투자금={order_krw:,}원"
+                f"수량={amount} | 투자금={order_krw:,}원 | trade_id={trade_id[:8]}"
             )
             notify_buy(ticker, actual_price, amount, order_krw)
             return True
@@ -318,7 +332,14 @@ def sell(ticker: str, reason: str = "") -> bool:
                     upsert_sell_price(ticker, current)  # DB 영구 저장
                 except Exception as e:
                     logger.error(f"직전 매도가 DB 저장 실패 {ticker}: {e}")
-            _update_history(ticker, pnl > 0, pnl)   # walk-forward 이력 갱신
+            _update_history(
+                ticker, pnl > 0, pnl, fee, krw_profit,
+                trade_id=pos.get("trade_id", ""),
+                buy_price=pos["buy_price"],
+                sell_price=current or pos["buy_price"],
+                invested_krw=pos["invested_krw"],
+                sell_reason=reason,
+            )
             del _positions[ticker]
             try:
                 delete_position(ticker)