release: prepare 2026.08.31-r2 CalVer image

[soulteary]

Summary

• prepare the next immutable CalVer candidate as 2026.08.31-r2
• retain and document 2026.08.31-r1 as a source-only failed release attempt
• align Dockerfile, validation, deployment, changelog, and release examples
• document the safe recovery path for a failed release preflight
• use the Asia/Shanghai project release date consistently

Why a new revision

The existing 2026.08.31-r1 ref is a lightweight tag and points to source that declares IMAGE_VERSION=2026.08.30-r1. Release run 33333864411 stopped in preflight before any image build.

The CalVer tag is already public, so this PR does not move, delete, or reuse it. After this PR is merged, publish 2026.08.31-r2 from a new annotated tag covered by the active CalVer tag ruleset.

Local verification

• bash -n docker-entrypoint-sqlite.sh scripts/*.sh tests/*.sh
• bash tests/test-documentation.sh
• bash tests/test-release-availability.sh
• bash tests/test-entrypoint-reconcile.sh
• git diff --check

PR CI remains the authority for PHP tests and the amd64/arm64/armv7 image smoke matrix.

Post-merge publication

git switch main
git pull --ff-only
release=2026.08.31-r2
git tag -a "${release}" -m "Release ${release}"
test "$(git cat-file -t "refs/tags/${release}")" = tag
git push origin "refs/tags/${release}"

Create the GitHub Release only after the protected workflow verifies both registries and signatures.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-08-30T22:34:33.740165Z	c31f14e	PR opened

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