docs: fix and annotate research links after link check

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/research/README.md

@@ -18,3 +18,12 @@ Background research ported from earlier work (2026-10-29) and sanitized for clea
 ## Intentionally excluded
 
 The original research also contained architecture notes produced from a source-code read of n8n, covering how its feature gating is implemented. They were left out on purpose and must not be brought into this repository. STaurtomation contributors must not read the source code of n8n, Kestra, Windmill or Activepieces, or of forks of them such as the sreent/n8n "tuflow" fork, and must not read descriptions derived from that source.
+
+## Link check (2026-10-30)
+
+All 151 links were checked with an automated HTTP request. Dead or unreachable links are marked
+inline. These returned 403/429/999 to scripted requests (bot blocking; likely fine in a browser, not
+verified): axios.com, linkedin.com, funding.tech.eu, lumadock.com, neura.market, news.hada.io,
+repos.ecosyste.ms (402), trademark.justia.com, dorsey.com, fieldfisher.com, g2.com, jenner.com,
+vondranlegal.com. A mintlify.com mirror of n8n's repository docs was replaced with the official
+docs.n8n.io page, and a third-party Authelia mirror with authelia.com.