message: docs(migration): document the onchange for radio-group
diff: @@ -624,6 +624,28 @@ Changed `color` prop to `colorScheme`.
  </RadioGroup>
  ```
  +- The `onChange` callback now returns the selected `value` not the `event`.
  +
  +```jsx live=false
  +const [value, setValue] = React.useState("one")
  +
  +// before
  +<RadioGroup value={value} onChange={e => setValue(e.target.value)}>
  + <Radio value="one">One</Radio>
  + <Radio value="two">Two</Radio>
  + <Radio value="three">Three</Radio>
  +</RadioGroup>
  +
  +// after
  +<RadioGroup value={value} onChange={val => setValue(val)}>
  + <Stack direction="row">
  + <Radio value="one">One</Radio>
  + <Radio value="two">Two</Radio>
  + <Radio value="three">Three</Radio>
  + </Stack>
  +</RadioGroup>
  +```
  +
  ## Slider
  - Update JSX structure: Wrap `SliderFilledTrack` with `SliderTrack`.
  