feat(strategy): Phase 2 complete — strategy infrastructure upgrade

- Technical indicators library (ATR, ADX, RSI, MACD, Bollinger, Stochastic, OBV)
- Signal model: conviction score, stop_loss, take_profit fields
- BaseStrategy: ADX regime filter, volume confirmation, ATR-based stops
- All 8 strategies upgraded with filters, conviction scoring, ATR stops
- Combined strategy uses conviction-weighted scoring
- 334 tests passing

1 files changed, 3 insertions, 1 deletions

diff --git a/services/strategy-engine/strategies/indicators/volatility.py b/services/strategy-engine/strategies/indicators/volatility.py
index d47eb86..c16143e 100644
--- a/services/strategy-engine/strategies/indicators/volatility.py
+++ b/services/strategy-engine/strategies/indicators/volatility.py
@@ -1,4 +1,5 @@
 """Volatility indicators: ATR, Bollinger Bands, Keltner Channels."""
+
 import pandas as pd
 import numpy as np
 
@@ -30,7 +31,7 @@ def atr(
         for i in range(period, n):
             atr_vals[i] = (atr_vals[i - 1] * (period - 1) + tr[i]) / period
 
-    return pd.Series(atr_vals, index=closes.index if hasattr(closes, 'index') else None)
+    return pd.Series(atr_vals, index=closes.index if hasattr(closes, "index") else None)
 
 
 def bollinger_bands(
@@ -62,6 +63,7 @@ def keltner_channels(
     Returns: (upper_channel, middle_ema, lower_channel)
     """
     from strategies.indicators.trend import ema as calc_ema
+
     middle = calc_ema(closes, ema_period)
     atr_vals = atr(highs, lows, closes, atr_period)
     upper = middle + atr_multiplier * atr_vals