[0.7.2] - 2026-03-05 - Gradient Fill Support

Added

• Gradient Fill (FillRenderer): Added support for Pine Script's gradient fill variant — fill(plot1, plot2, top_value, bottom_value, top_color, bottom_color). The renderer detects plotOptions.gradient === true and renders each polygon segment with a vertical ECharts linear gradient, mapping top_color to the higher-value boundary and bottom_color to the lower-value boundary. Gracefully falls back to a semi-transparent grey if per-bar color data is missing.
• ColorUtils.toRgba(): Added a new utility method to convert any parsed color + opacity pair into a reliable rgba() string, handling rgb(), 6-digit hex, and 8-digit hex (#RRGGBBAA) inputs.
• ColorUtils.parseColor() — 8-digit Hex: Extended parseColor() to handle #RRGGBBAA colors (the format PineTS emits for color.new() with alpha), correctly extracting the alpha channel as opacity.

Fixed

• Fill References Broken by color: na: Fixed fill plots losing their reference data when the source plot had segments with color: na (invisible segments). Previously, plotDataArrays stored the post-nullification array (where na-color points were set to null), so the fill had gaps wherever the source plot was invisible. Now a separate rawDataArray is stored with the original numeric values, ensuring fills always see the underlying data regardless of visibility.