Convert static-site from Pages Router to App Router

[genehack]

This is a prerequisite for #134, but has expanded beyond that to the point where I think a distinct isuse will be helpful. This should be considered a meta-issue, to facilitate building on top of the initial conversion work to parallelize work to finalize the conversion.

This is a list of pages that need to be converted:

• index page
  • components/SEO
    • requires porting to Metadata API
  • components/splash
    • has a fair number of moving parts at least some of which (e.g., ExpandableTiles) overlap with other components (e.g., ListResources) — might be easiest to leave this for the end
• 404/not-found
• /blog
  • Port /blog to App router; add blog preview cards [#134] #1059
• /community and /community/[[...community]]
  • components/Datasets/dataset-select
  • components/errorMessages
• /contact
• /groups
  • components/Datasets/dataset-select
  • components/errorMessages
  • components/Groups/Tiles
  • components/ListResources
• /groups/[[...groupName]]
  • This is actually three pages (IndividualGroupPage, GroupMembersPage, GroupSettingsPage) in a trenchcoat
• /ncov/[[..ncov]]
  • DatasetSelect
  • DatasetMap
  • SituationReportByLanguage
    • CollapseTitle
    • DataFetchErrorParagraph
  • PathogenPageIntroduction
  • ErrorBanner
• Convert /pathogens to App Router #1066 @genehack
• /sars-cov-2/[[...sars-cov-2]]
  • Almost identical to /ncov/[[...ncov]]
• /sars-cov-2/forecasts
  • If this can be done independently of /sars-cov-2/[[...sars-cov-2]] (unclear to me without experimentation), this is a very small lift
• Convert /staging/[[...staging]].jsx to App Router #1067
  • blocks on Convert /pathogens to App Router #1066
• /team
• /whoami

If you'd like to build on top of #1032 and convert one of these pages, please create a new issue and then link that issue to the appropriate page in the above list.

In many cases, converting one of these will also require porting a component away from using Styled Components; some of these components may be used across more than one top-level page (e.g., is used by /groups, /pathogens, and /staging). Before you start working on converting a page, please make sure that somebody isn't already working on a page that would require both of you working on the same underlying component! To make it a little easier to see where these overlaps are, I have listed some of the components used in particular pages as sub-items of the page.