feat: finalize portfolio system and quantitative validation- Finalized MA_Crossover(30,100) and TrendFiltered_MA(30,100,ADX=15)

- Implemented portfolio engine with risk-based allocation (50/50)
- Added equity-based metrics for system-level evaluation
- Validated portfolio against standalone strategies
- Reduced max drawdown and volatility at system level
- Quantitative decision closed before paper trading phase

tests/test_walkforwad.py

@@ -15,7 +15,7 @@ sys.path.insert(0, str(Path(__file__).parent.parent))
 from src.utils.logger import log
 from src.data.storage import StorageManager
 from src.strategies import MovingAverageCrossover
-from src.backtest.walk_forward import WalkForwardValidator
+from src.core.walk_forward import WalkForwardValidator
 
 
 def setup_environment():