feat: add market regime filter and compound reinvestment

- Add market_regime.py: BTC/ETH/SOL/XRP weighted 2h trend score
  Bull(≥+1.5%) / Neutral / Bear(<-1%) regime detection with 10min cache
- strategy.py: dynamic TREND/VOL thresholds based on current regime
  Bull: 3%/1.5x, Neutral: 5%/2.0x, Bear: 8%/3.5x
- price_collector.py: always include leader coins in price history
- trader.py: compound reinvestment (profit added to budget, floor at initial)
- notify.py: regime info in hourly report, P&L icons (✅/❌, 💚/🔴)
- main.py: hourly status at top-of-hour, filter positions held 1h+
- backtest.py: timestop/combo comparison modes

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

core/price_db.py

@@ -206,6 +206,15 @@ def record_trade(
         )
 
 
+def get_cumulative_krw_profit() -> float:
+    """전체 거래 누적 KRW 손익 반환 (수수료 차감 후). 데이터 없으면 0."""
+    with _conn() as conn:
+        cur = conn.cursor()
+        cur.execute("SELECT SUM(krw_profit) FROM trade_results WHERE krw_profit IS NOT NULL")
+        row = cur.fetchone()
+    return float(row[0]) if row and row[0] is not None else 0.0
+
+
 def load_recent_wins(ticker: str, n: int = 5) -> list[bool]:
     """직전 N건 거래의 승/패 리스트 반환 (오래된 순). 없으면 빈 리스트."""
     sql = """