Eight cloud.google.com documentation links across 7 skills return 404

[ayobamiseun]

A link check across all skill markdown files found 8 unique cloud.google.com documentation URLs that return HTTP 404 (verified twice, following redirects). These appear in the "references"/further-reading sections that agents and users are directed to. In each case a current working page exists — the docs have moved.

File:line	Dead link (404)	Working replacement (200)
skills/cloud/gke-platform-security/SKILL.md:195	https://cloud.google.com/kubernetes-engine/docs/how-to/secret-manager	https://cloud.google.com/secret-manager/docs/secret-manager-managed-csi-component
skills/cloud/gke-platform-security/SKILL.md:196	https://cloud.google.com/binary-authorization/docs/getting-started-gke	https://cloud.google.com/binary-authorization/docs/setting-up
skills/cloud/gke-platform-security/SKILL.md:198	https://cloud.google.com/kubernetes-engine/docs/concepts/sandbox	https://cloud.google.com/kubernetes-engine/docs/how-to/sandbox-pods
skills/cloud/gke-workload-security/SKILL.md:239	https://cloud.google.com/kubernetes-engine/docs/how-to/pod-security-standards	https://cloud.google.com/kubernetes-engine/docs/how-to/podsecurityadmission
skills/cloud/gke-workload-security/SKILL.md:240	https://cloud.google.com/kubernetes-engine/docs/how-to/secret-manager	https://cloud.google.com/secret-manager/docs/secret-manager-managed-csi-component
skills/cloud/gke-upgrades/SKILL.md:211	https://cloud.google.com/kubernetes-engine/docs/how-to/rollout-sequencing	https://cloud.google.com/kubernetes-engine/docs/concepts/about-rollout-sequencing
skills/cloud/google-cloud-global-frontend-configuration/SKILL.md:125	https://cloud.google.com/load-balancing/docs/overview	https://cloud.google.com/load-balancing/docs
skills/cloud/alloydb-basics/references/mcp-usage.md:25	https://cloud.google.com/alloydb/docs/reference/	https://cloud.google.com/alloydb/docs/reference/rest
skills/cloud/bigtable-basics/SKILL.md:115	https://cloud.google.com/bigtable/docs/reference/sql	https://cloud.google.com/bigtable/docs/googlesql-overview

The suggested replacements are pages verified to return 200 today that cover the same topic — the responsible teams may know a more canonical target.

Repro

for u in \
  https://cloud.google.com/kubernetes-engine/docs/how-to/secret-manager \
  https://cloud.google.com/binary-authorization/docs/getting-started-gke \
  https://cloud.google.com/kubernetes-engine/docs/concepts/sandbox \
  https://cloud.google.com/kubernetes-engine/docs/how-to/pod-security-standards \
  https://cloud.google.com/kubernetes-engine/docs/how-to/rollout-sequencing \
  https://cloud.google.com/load-balancing/docs/overview \
  https://cloud.google.com/alloydb/docs/reference/ \
  https://cloud.google.com/bigtable/docs/reference/sql; do
  echo "$(curl -s -o /dev/null -w '%{http_code}' -L "$u") $u"
done

Related: #205 (broken relative links; this issue covers broken external links).