v1.55.0

Added

• Radial backgroundGradient — GradientBackground is now a discriminated union of linear and radial. A radial gradient is { type: "radial", center?: { x, y }, radius?, stops }: center is in 0–1 box fractions (default { 0.5, 0.5 }), radius is a 0–1 box fraction (default 0.75), and each stop is { color, position? } (same as linear). Available on every element via BaseBoxProps. Existing linear gradients are unchanged.

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