Day Color Candles

The script uses TradingView’s built-in dayofweek value (where Monday = 1 and Sunday = 7) to detect the current bar’s weekday.
For each weekday, a specific color is assigned — green for Monday, blue for Tuesday, purple for Wednesday, orange for Thursday, yellow for Friday, gray for Saturday, and red for Sunday.

Instead of plotting new candles, the script uses barcolor() to recolor the existing chart candles. This avoids conflicts with TradingView’s rule that a script may contain only one main declaration. The price data remains unchanged — only the visual appearance of the candles is modified to help the user visually separate trading days.