* Add local eslint rule to validate markdown codeblocks with React Compiler
In https://github.com/facebook/react/pull/34462 for example, we found an issue where the compiler was incorrectly validating an example straight from the docs.
In order to find more issues like this + also provide more feedback to doc authors on valid/invalid patterns, this PR adds a new local eslint rule which validates all markdown codeblocks containing components/hooks with React Compiler. An autofixer is also provided.
To express that a codeblock has an expected error, we can use the following metadata:
```ts
// pseudo type def
type MarkdownCodeBlockMetadata = {
expectedErrors?: {
'react-compiler'?: number[];
};
};
```
and can be used like so:
````
```js {expectedErrors: {'react-compiler': [4]}}
// ❌ setState directly in render
function Component({value}) {
const [count, setCount] = useState(0);
setCount(value); // error on L4
return <div>{count}</div>;
}
```
````
Because this is defined as a local rule, we don't have the same granular reporting that `eslint-plugin-react-hooks` yet. I can look into that later but for now this first PR just sets us up with something basic.
* fix compiler errors
I went through the list of existing errors and tried to separate the expected errors from those that seem to be flagging unexpected issues. In particular, our effects validations are flagging patterns that our own docs examples use. I added todos for these and will follow up later.
The previous sentence "If you are using React Compiler, useMemo, useCallback, and React.memo can be removed." was coming off a bit too strong and makes it incorrectly seem like the manual memos and compiler memos are 1:1.
Removing the sentence doesn't take anything away from this paragraph, so let's remove it to reduce confusion.
* Fix deadlinks take 2
Fixes the actual broken links.
```
$ yarn deadlinks
yarn run v1.22.22
$ node scripts/deadLinkChecker.js
Checking 177 markdown files...
Fetched 552 React error codes
Loaded 49 redirects from vercel.json
✓ All 1554 links are valid!
✨ Done in 0.86s.
```
* [compiler] Rewrite React Compiler Docs
We've received [feedback](https://bsky.app/profile/danabra.mov/post/3lr46ciujjs2r) that the compiler docs are difficult to understand and not prominent enough that people don't realize the compiler is a serious project and is near stable.
This PR rewrites the whole compiler doc section, giving it its own category as well as a standalone reference page.
Preview: https://react-dev-git-pr7868-fbopensource.vercel.app/
