The spread parameter in the Backtest class currently accepts only a float value. Allow the spread to be either a numpy array or a required column in the data DataFrame, as spread is typically different per row of the OHLC dataframe.
### Enhancement description so I was looking at the Backtest class and it accepts `spread: float = .0,` which is as far as I know spread is different per row and it's not fixed. I'm looking forward to the spread to be either np array or a required column in `data: pd.DataFrame,`. ### Additional info, images this is what Mt5 return so as you notice the spread has it's own column because it's dynamically changing depending on time. ``` First 5 rows: Open High Low Close Volume spread real_volume time 2025-04-16 22:00:00 1.13864 1.14128 1.13847 1.13865 6294 8 0 2025-04-16 23:00:00 1.13866 1.13992 1.13816 1.13981 2788 8 0 2025-04-17 00:00:00 1.13980 1.13994 1.13939 1.13964 627 21 0 2025-04-17 01:00:00 1.13971 1.13997 1.13943 1.13995 1461 8 0 2025-04-17 02:00:00 1.13995 1.14093 1.13940 1.13955 2776 8 0 2025-04-17 03:00:00 1.13959