ci: Cat 1072 security nightly cleanup

[shortstacked]

Summary

• Includes CVE details in scan slack message
• Uses slack official action instead of 3rd party action
• Adds detailed summary report to the Github action using Github Summaries
• No longer sends on successful check, but will still add summary.

Related Linear tickets, Github issues, and Community forum posts

https://linear.app/n8n/issue/CAT-1072/ci-remove-positive-result-from-nightly-security-scan

Review / Merge checklist

• PR title and summary are descriptive. (conventions)
• Docs updated or follow-up ticket created.
• Tests included.
• PR Labeled with release/backport (if the PR is an urgent fix that needs to be backported)

[cubic-dev-ai]

cubic analysis

1 issue found across 2 files • Review in cubic

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[cubic-dev-ai]

Invalid two-parameter call to sort_by will make the Slack-block jq script crash, so no Slack message will be posted.

Prompt for AI agents

Address the following comment on .github/workflows/security-trivy-scan-callable.yml at line 178:

<comment>Invalid two-parameter call to sort_by will make the Slack-block jq script crash, so no Slack message will be posted.</comment>

<file context>
@@ -4,123 +4,206 @@ on:
   workflow_dispatch:
     inputs:
       image_ref:
-        description: Full image reference to scan e.g ghcr.io/n8n-io/n8n:latest
+        description: &#39;Full image reference to scan e.g. ghcr.io/n8n-io/n8n:latest&#39;
         required: true
         default: &#39;ghcr.io/n8n-io/n8n:latest&#39;
   workflow_call:
     inputs:
</file context>

Suggested change

	sort_by((.Severity == "HIGH" | if . then 1 else 0 end), -((.CVSS.nvd.V3Score // 0) | tonumber? // 0)) |
	sort_by([(.Severity == "HIGH" | if . then 1 else 0 end), -((.CVSS.nvd.V3Score // 0) | tonumber? // 0)]) |