OptionallineStroke width in pixels. When omitted, falls back to ToolsOptions.lineWidth.
OptionallineStroke color. When omitted, falls back to ToolsOptions.lineColor.
OptionalopacityObject opacity as a percentage (0–100).
OptionalrotationObject rotation in degrees.
OptionalfillFill color.
Use 'transparent' or a color with zero alpha for outline-only rectangles.
When omitted, falls back to ToolsOptions.fillColor.
OptionalborderCorner radius in pixels. Use 0 for sharp corners.
Default style options for Rectangle objects.