* turn article.scss into a module + componentized
* Update Survey to use only component styles, add cancel button
* Update GenericError + 404 page to use only standard classes
* update LearningTrack to not use markdown-body
* remove / consolidate stylesheets
* cleanup Graphiql explorer page and scss
* Componentize Breadcrumb styles
* Componentize DeprecationBanner styles
* scope h2 a link style to markdown-body
* cleanup nav, organize page-header and page-footer components
* remove unused scroll-button.scss
* organize LanguagePicker and ProductPicker
* add declarations file
* remove featured-links.scss, update tests
* update list utility and toc test
* fix bad merge resolution
* update breadcrumbs test
* start SidebarNav, enable dark mode
* wip: sidebarnav, fix primer components theme rendering
* feat: ProductSiteTree, useFeatureFlag
* feat: add new product site tree (untested)
* wire up HomepageVersionPicker, run lint
* fix: remove re-render logic, fix homepage version picker to be natural width
* fix: support css + primer/components color modes
* fix: rename categoryId -> productId
* feat: ProductSiteTree and AllArticlesProduct
* fix: cleanup warnings
* fix: use next links on ProductSiteTreeNew
* fix: use next Link on AllArticlesProduct
* fix: add tooltip to ScrollButton, remove stylesheet dependency
* feat: ProductArticlesList component
* fix: convert color_mode value from cookie when necessary
* remove comments
* replace liquid with jsx
Co-authored-by: Rachael Sewell <rachmari@github.com>