DialogButton

Specification for a dialog button.

Attributes:

Name	Type	Description
`text`	`str`	Button label text displayed to the user.
`role`	`ButtonRole`	Button role determining styling and behavior. - `"primary"`: Main action (blue, triggered by Enter) - `"secondary"`: Standard action (gray) - `"danger"`: Destructive action (red) - `"cancel"`: Cancel action (outline, triggered by Escape) - `"help"`: Help/info action (link style)
`result`	`Any \| None`	Value assigned to dialog.result when clicked.
`closes`	`bool`	Whether button closes the dialog when clicked.
`default`	`bool`	Whether this is the default button (focused, triggered by Enter).
`command`	`Callable[[Dialog], None] \| None`	Callback called when clicked.
`accent`	`str \| None`	Accent token for styling (e.g., 'primary', 'danger').
`variant`	`str \| None`	Style variant (e.g., 'outline', 'link').
`icon`	`str \| dict \| None`	Optional icon specification for the button.