Standardize name for "splat" URL elements?

[genehack]

I wonder if another name would be more informative here. Maybe staging/[[...slug]]/… to match Next.js docs? Same would go for pathogens/[[...slug]]. blog/[id] is meaningful as-is.

  if (params && params["slug"]) {
    notFound();
  }

Not the fault of this PR since the old implementation uses [[...staging]]

Originally posted by @victorlin in #1131 (comment)

[victorlin]

path is now the standard with the switch to dynamic routes.

$ find . -type d -name '*\[...*'    
./static-site/static-site/app/staging/[...path]
./static-site/app/staging/[...path]
./static-site/app/nextclade/[...path]
./static-site/app/pathogens/[...path]
./static-site/app/groups/[group]/[...path]
./static-site/app/ncov/[...path]
./static-site/app/sars-cov-2/[...path]
./static-site/app/community/narratives/[user]/[repo]/[...path]
./static-site/app/community/[user]/[repo]/[...path]