--fix-moved rewrites only the inline and angle-bracket link forms #1278

Where: scripts/check_external_links.py (fix_moved).

Current gap: Only ](URL) and <URL> are replaced. A link with a title (](URL "title")), a reference definition ([ref]: URL) or an HTML href="URL" in a markdown file is reported as moved but left unchanged, so the report keeps listing it.

Suggested approach: Extend the replacement to those forms, using the same URL boundaries, and test each.

Done when: a document using all five forms has every moved link rewritten and nothing else changed.