Check the documentation links instead of reporting success on nothing

[woksin]

Fixed

• Documentation link verification checks links again — it reported success while scanning zero links, both locally and in CI (verify-markdown.sh reports success while scanning zero links #2416)
• Fourteen documentation links that named pages under a file name those pages no longer have

[woksin]

Reviewer context — deliberately kept out of the description.

This is agent-authored and no human has read it yet. Green CI is not sign-off.

The cause was not the glob

The issue guessed a glob or working-directory mismatch. It is neither. linkinator serves the files it scans from a local web server on 127.0.0.1, so every internal link resolves to http://127.0.0.1:<port>/…. The skip pattern ^(https?:\/\/)?(localhost|127\.0\.0\.1)(:\d+)?(\/|$) therefore matched the crawl root itself, the whole scan was skipped, and the run reported success:

✓ Successfully scanned 0 links in 0.011 seconds.   (exit 0)

The same pattern is passed to linkinator-action in the workflow, so CI was equally blind — run 30450036709 logs Scanned total of 0 links!.

What is verified here and what is not

A single repository can only resolve relative links and external URLs. Links written as site-absolute paths (/arc/…, /chronicle/…) address the aggregated site, where each product's Documentation folder is mounted under its own prefix; they are verified when that site is built. The skip is now expressed as a rule — "served by our own scan server and outside /Documentation/" — so a new product prefix needs no change here.

Verification

	Before	After
links scanned	0	317
broken links reported	0	0 (14 found and fixed)

• Pre-fix configuration passes with a broken link present — a scratch page with a dead link, old flags: Successfully scanned 0 links, exit 0.
• New script fails on the same page — Detected 1 broken links. Scanned 319 links, exit 1.
• Zero-scan guard — restoring the old skip pattern in a copy of the script now exits 1 with Link verification scanned zero links, rather than passing.
• No-summary guard — globs matching nothing exits 1 rather than passing.
• Documentation/verify-markdown.sh passes end to end (lint 259 files + links 317), from the repository root and from Documentation/.

The fourteen links

Five kept .md after the page became .mdx (add-event-sourcing, your-first-command, frontend/index, storybook) — those resolve nowhere, on the site or off it. Nine were extensionless chapter links in the tutorial, which the site resolves but a file-level check cannot; they now carry the file name like the rest of the documentation does (generating-a-screenplay.md already links .mdx this way).

Worth knowing

• Every folder under Documentation/ currently has an index page, so --directory-listing is equivalent to a strict check today. If a folder ever loses its index page, a link to that folder would pass here — the aggregated site build is what catches that.
• linkinator is pinned to 8.0.2 so a new major cannot silently change what is scanned.
• .mdx pages are now scanned for links (13 files, +18 links). They are still not linted — markdownlint runs on *.md only, unchanged by this PR.