Polynomial Regression with RSI & Volume Profile

Plotting the Polynomial Regression Line: The plot(polyLine) function now ensures that the regression line is drawn on the chart.
Buy and Sell Signals: plotshape() is used to plot buy and sell signals on the chart when the respective conditions are met.
Volume Profile and Polynomial Regression: These components now have their visual output on the chart, ensuring that the script is valid and contains the necessary plot statements