With this PR, you can now customize the way that `blocks` and
`inlineBlocks` are rendered within Lexical's `BlocksFeature` by passing
your own React components.
This is super helpful when you need to create "previews" or more
accurate UI for your Lexical blocks.
For example, let's say you have a `gallery` block where your admins
select a bunch of images. By default, Lexical would just render a
collapsible with your block's fields in it. But now you can customize
the `admin.components.Block` property on your `block` config by passing
it a custom React component for us to render instead.
So using that, with this `gallery` example, you could make a dynamic
gallery React component that shows the images to your editors - and then
render our built-in `BlockEditButton` to allow your editors to manage
your gallery in a drawer.
Here is an example where the BlockEditButton is added to the default
Block Collapsible/Header:
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Co-authored-by: James <james@trbl.design>
All payload css is now encapsulated inside CSS layers under `@layer
payload-default`
Any custom css will now have the highest possible specificity.
We have also provided a new layer `@layer payload` if you want to use
layers and ensure that your styles are applied after payload.
To override existing styles in a way that the existing rules of
specificity would be respected you can use the default layer like so
```css
@layer payload-default {
// my styles within the payload specificity
}
```
