softly support exactOptionalPropertyTypes by being explicit about when passing undefined to a property is okay

[akomm]

When enabled exactOptionalPropertyTypes in tsconfig, example:

This is because checked is defined as follows:

interface MenuCheckboxItemProps extends MenuItemProps {
    checked?: CheckedState;
    onCheckedChange?: (checked: boolean) => void;
}

By being explicit about undefined acceptance on optional properties, you could both enable support for the feature disabled and enabled at the same time:

interface MenuCheckboxItemProps extends MenuItemProps {
    checked?: CheckedState | undefined;
    onCheckedChange?: (checked: boolean) => void;
}

Since the component does work with undefined being passed to it and its compatible, adding | undefined should be 100% always fine. But developers who have the option enabled can write code that differs in this terms, but still can use your library.