A rounded rectangle draws a panel with softened corners, like a card or input field. Increasing the rounding takes it from a box toward a capsule-shaped button.
`width` and `height` are half-sizes, not full dimensions, and each ranges from 0.01 to 1. `rounding` is the corner radius from 0 to 0.5; setting it to the smaller of `width` and `height` makes a pill shape. `rotation` turns the shape from 0 to 360 degrees.
Remember that `width` and `height` are half-sizes, or the panel may be larger than expected. Use it as a card base, then add a small `strokeThickness` or a `Line` for an outline or divider.
When to use
Use it for card, input-field, and capsule-button backgrounds. Avoid it when you need a slanted edge or different top and bottom widths; choose Parallelogram or Trapezoid instead.