Option to output absolute URLs for internal links at build time

[mellymoyer]

We use root-relative links (/docs/whatever) across our docs, per the linking guide. Works great for us, but it turns out Claude can't follow them. Its web fetch only follows absolute URLs it's already seen, so it won't resolve /docs/whatever against the base domain on its own. If a page is only linked relatively and doesn't happen to show up in web search results, Claude just can't get to it. Sometimes it'll go search for the full URL and recover, but when that fails, discovery stops.

What we'd like is a config option that keeps links relative in the source but rewrites them to absolute in the prod build.

We're planning to just convert all our source files to absolute and adding a CI check to keep them that way, but there were two drawbacks:

1. Every link in localhost and Vercel previews would point at prod, which makes testing any navigation change painful
2. The built-in link checker assumes relative links, so we'd lose that (and potentially need to create our own)

Anyone else seeing this, or is there a workaround I'm missing? Thanks!