Fix Author Permalink Structure for Consistency and SEO on 11ty Site

[reatlat]

This pull request fixes an issue with the author permalink structure on the 11ty website, caused by differences in case sensitivity between Netlify and Vercel. Netlify handles URLs in a case-tolerant manner, automatically forcing them to lowercase, which ensured that links like

• https://www.11ty.dev/authors/MartyNZ/ [200]
• https://www.11ty.dev/authors/ItsMeAra/ [200]

worked seamlessly. However, on Vercel, URLs are case-sensitive, which led to inconsistencies and broken links when author slugs were not uniformly lowercase.

Current https://www.11ty.dev/authors/ page contains all links in lowercase format like this

• https://www.11ty.dev/authors/martynz/ [404]
• https://www.11ty.dev/authors/itsmeara/ [404]

To resolve this, the author permalink structure has been updated to enforce lowercase formatting using a slug filter. This change ensures all author URLs are consistently lowercase, preventing broken links and ensuring proper routing on Vercel’s deployment environment.

By standardizing URLs, this update enhances both user experience and SEO, ensuring predictable, functional, and clean author page links across the site.

[Snapstromegon]

The described issue is correct and IMO this is also the right change, but just to make this sure, I'm looping in @zachleat.

Either way: Thanks @reatlat for bringing this up and also providing a fix.

[reatlat]

Another optimal solution is edit vercel.config to something like

{
  "rewrites": [
    {
      "source": "/:path*",
      "destination": "/:path*",
      "has": [
        {
          "type": "header",
          "key": "x-original-url",
          "value": "/.*[A-Z]+.*/"
        }
      ]
    }
  ],
  "redirects": [
    {
      "source": "/(.*[A-Z].*)",
      "destination": "/$1",
      "statusCode": 301
    }
  ]
}