feat: migrate React.dev to the App Router (#7437)

* update version to latest + move folders around

* getting home page working

* make the mdx setup work

* bypass mdxname

* split out mdx components

* re-add meta mdx logic

* replace mdxName usage

* fix code blocks

* fix max width

* convert mdx post processing to actual plugins

* fix tailwind

* fix incorrect iframe props

* cleanup mdx dic

* make it actually build

* align fonts

* fix uwu script

* fix search

* remove _app

* make it actually build

* replace next-watch-remote with custom setup

* clean up logs + clean up inline scripts

* add rss handler

* remove rss generation

* remove rss generation

* support MDX components for TOC

* clean up log + bump cache

* fix toc

* add back translations + add new overlay

* use MDX link instead of Next.js links for translation

* fix analytics

* add myself to the contributors

* fix blinking sidebar

* avoid rendering toc on the client

* plugin metadata

* simplify metadata

* fix title

* clean up metadata

* add back error decoder

* Update src/content/learn/index.md

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Co-authored-by: Ricky <rickhanlonii@gmail.com>

scripts/generateRss.js

@@ -1,6 +0,0 @@
-/*
- * Copyright (c) Facebook, Inc. and its affiliates.
- */
-const {generateRssFeed} = require('../src/utils/rss');
-
-generateRssFeed();