OSDOCS-22244: Add 4.18.55 z-stream release notes (advisory-only)

[bjahagir-OpenShift]

Summary

• Adds z-stream release notes for OCP 4.18.55 (ADVISORY-ONLY)
• Jira: https://redhat.atlassian.net/browse/OSDOCS-22244
• Shipment MR: https://gitlab.cee.redhat.com/hybrid-platforms/art/ocp-shipment-data/-/merge_requests/817
• Errata: RHSA-2026:65852

Documented

None - Advisory-only release

Jira RN text populated (Step 3a)

• Auto-closed: 30/30 issues (29 RN-NR, 1 Red Hat Employee)

Scope notes

• Shipment YAML keys: 35
• Documented: 0 (advisory-only)

Test plan

• Vale clean (0 errors)
• Update issued date when errata published

🤖 Generated with Claude Code

[openshift-ci-robot]

@bjahagir-OpenShift: This pull request references OSDOCS-22244 which is a valid jira issue.

Details

In response to this:

Summary

• Adds z-stream release notes for OCP 4.18.55 (ADVISORY-ONLY)
• Jira: https://redhat.atlassian.net/browse/OSDOCS-22244
• Shipment MR: https://gitlab.cee.redhat.com/hybrid-platforms/art/ocp-shipment-data/-/merge_requests/817
• Errata: RHSA-2026:65852

Documented

None - Advisory-only release

Jira RN text populated (Step 3a)

• Auto-closed: 30/30 issues (29 RN-NR, 1 Red Hat Employee)

Scope notes

• Shipment YAML keys: 35
• Documented: 0 (advisory-only)

Test plan

• Vale clean (0 errors)
• Update issued date when errata published

🤖 Generated with Claude Code

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[ocpdocs-previewbot]

🤖 Tue Sep 15 17:59:21 - Prow CI generated the docs preview:

https://119842--ocpdocs-pr.netlify.app/openshift-enterprise/latest/release_notes/ocp-4-18-release-notes.html

[ocpdocs-vale-bot]

🤖 [error] OpenShiftAsciiDoc.NoXrefInModules: Do not include xrefs in modules, only assemblies (exception: release notes modules).

[openshift-ci]

@bjahagir-OpenShift: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/validate-portal	1cf0589	link	true	/test validate-portal

Full PR test history. Your PR dashboard.

Details

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