The `<Menu />` component. Implemented using
[useMenu](https://react-spectrum.adobe.com/react-aria/useMenu.html) from React-Aria.

## Content

The `<Menu />` element follows the
[Collection Components API](https://react-spectrum.adobe.com/react-stately/collections.html) from
the `@react-stately` library, accepting both static and dynamic collections. `<Menu />` accepts
`<Item />` elements as children, each with a key prop. Basic usage of `<Menu />`, seen in the
example below, shows multiple options populated with a string. Simple element with simple options as
text.

## Simple example

Usually used in `<MenuTrigger />`;

```js
<Menu selectionMode="single">
  <Item key="one">One</Item>
  <Item key="two">Two</Item>
  <Item key="three">Three</Item>
</Menu>
```

## Dynamic Content

An iterable list of options is can be passed to the `<Menu />` using the items prop. Each item
accepts a key prop, which is passed to the `onSelectionChange` or `onAction` handler to identify the
selected item. Alternatively, if the item objects contain an `id` property like in the example
below, then this is used automatically and a key prop is not required.

```js
import { Item } from '@react-stately/collections';

const options = [
  { id: 1, value: 'One' },
  { id: 2, value: 'Two' },
  { id: 3, value: 'Three' },
  { id: 4, value: 'Four' },
]

<Menu onAction={(key) => console.log} items={options}>
  {(item) => <Item>{item.value}</Item>}
</Menu>
```

## Sections

`<Menu />` supports sections in order to group options. Sections can be used by wrapping groups of
items in a `<Section />` element. Each `<Section />` takes a title and key prop.

```js
import { Item, Section } from '@react-stately/collections';

<Menu onAction={(key) => console.log}>
  <Section title="Colors">
    <Item>Red</Item>
    <Item>Blue</Item>
    <Item>Green</Item>
    <Item>Yellow</Item>
  </Section>
  <Section title="Animals">
    <Item>Dog</Item>
    <Item>Cat</Item>
  </Section>
</Menu>;
```