SonarCloud: flip the PR summary-comment toggle to complete the D4 mute (sonarcloud.io UI, maintainer-only)

[hyperpolymath]

Context

Decision D4 (merged in #53) is fully recorded in-repo: docs/ci/sonarcloud-pr-comments.adoc, plus STATE.a2ml, PLAYBOOK.a2ml, and an AGENTIC.a2ml guard. The in-repo half is done.

The sonarqubecloud[bot] "Quality Gate passed" summary comment that lands on every PR (e.g. #52, #53, #54, #55) is produced server-side by the SonarQube Cloud GitHub App. There is no repository-side property that can mute it (the sonar.pullrequest.github.summary_comment key is SonarQube Server-only, not Cloud). So the final step is a one-time admin action that can't be committed and only the maintainer can perform.

Action (one-time, ~30s)

Requires SonarQube Cloud Administer permission on project hyperpolymath_svalinn:

1. https://sonarcloud.io → project hyperpolymath_svalinn
2. Administration → General Settings → Pull Requests
3. Turn off "Enable analysis summary under the GitHub Conversation tab" (older label: "Enable summary comment")
4. Save — analysis keeps running and still reports under Checks; the bot just stops commenting.

Verification / acceptance

• Next PR shows no sonarqubecloud[bot] summary comment
• SonarCloud quality gate still appears under the PR Checks tab

Full runbook: docs/ci/sonarcloud-pr-comments.adoc.