Migrate RN website from v1 to v2

[teikjun]

To do list

• Run migration CLI
• Remove unused versions
• remove from /versioned_docs, /versioned_sidebar, versions.json, docusaurus.config.js
• Fix build errors from all versioned_docs and current docs
• close all unclosed tags, remove invalid tags (handled by Backwards compatible docs fixes for docusaurus upgrade react/react-native-website#2158)
• for any invalid JSX outside codeblocks, enclose them in codeblocks (handled by Backwards compatible docs fixes for docusaurus upgrade react/react-native-website#2158)
• use MDX compatible syntax: change class to className, change style="..." to style={{...}}.
• Fix other build errors
• Fix url-loader issue by adding it as dependency in root directory ( as a hack )
• Fix errors in blog
• Migrate navbar items
• Migrate footer items
• Migrate pages for help, showcase, version
• replace CompLibrary, siteConfig and other deprecated things with appropriate substitutes
• In docusaurus.config.js, set preset-classic's pages.path to be 'pages/en'
• Migrate CSS for pages and docs
• Use CSS modules to limit scope of CSS (global CSS can affect theme components)
• Remove incompatible CSS and fix bugs
• Move assets (handled by move image assets from docs to statics folder react/react-native-website#2157)
• Move /docs/assets into /static/docs/assets
• Move missing images from /blog/assets into /static/blog/assets
• Migrate landing page
• Fix CSS bugs in landing page
• Customize Prism setup and SnackPlayer using remarkablePlugins 🔨
• Fix custom CSS components in docs
• Fix tabbed items in docs 🔨
• Replace quotes with admonitions in docs
• Add redirects for moved/renamed docs

Test site
https://reactnative-v2.netlify.app/docs/

Active branches:
docs/v2-migration - We're working on this branch!
docs/master - our base branch (before any migration)

Inactive branches (may be useful for reference):
docs/migration - ran cli without flags. A new branch was needed because this one does not preserve git history
docs/2-migration - ran cli with --page --mdx, use this as reference

Legends:

🔨 - in progress

• - complete

Note: After ticking each item, we'll add a more detailed log and group similar items. Also, TJ should relay this todo to RN repo.

Issues that need to be fixed on CLI:

• use relative path for presets.docs.sidebarPath, presets.theme.customCss
• says subcategory instead of category

[darshkpatel]

Alright! Finally fixed all the issues with the site without adding extra commits.
PS. I swear this is the last force push. I'm done rebasing stuff

[darshkpatel]

Updated the blog paths in the previous commits to reflect upstream master changes

[darshkpatel]

SnackPlayer works now 🥳

[darshkpatel]

Note: Index page has an issue currently, browsing http://localhost:3000/docs/ will help

[teikjun]

bugs to squash:

• "exports" error at index page and versions page

• this may be related to const docusaurusConfig = require('../../docusaurus.config.js'); which may be treated as mixing es6 and commonjs syntax.

• gray boxes in place of snack player (e.g. at docs/styles)

• not sure about this atm

[darshkpatel]

• gray boxes in place of snack player (e.g. at docs/styles)

Apparently refreshing the page fixes it