use gpui::DefiniteLength; /// A trait for elements that can have a fixed with. Enables the use of the `width` and `full_width` methods.pub trait FixedWidth {    /// Sets the width of the element.    fn width(self, width: impl Into<DefiniteLength>) -> Self;     /// Sets the element's width to the full width of its container.    fn full_width(self) -> Self;}