ci: remove the automatic release back-merge

[kixelated]

Problem

Every push to release opens a PR merging release back into main, landed by Check's land job as a moq-bot --admin merge commit. That machinery needs a bot bypass on the planned squash queue, a workflows permission for moq-bot, and an unreviewed path past the queue. The maintainer decided (2026-10-10) it isn't worth it:

remove it, we can just cherry pick from main to release

once merge release into main before a semver release

Approach

• Delete .github/workflows/back-merge.yml, sh/gh/back-merge.sh, the just gh back-merge recipe, Check's land job, and the Back-merge entry in alert.yml.
• CONTRIBUTING.md: fixes still land on main and are cherry-picked onto release. Nothing merges release into main automatically; before a minor or breaking release, the maintainer merges release into main once, as a merge commit with --admin (the only allowed queue bypass), then cuts as today.
• Quests: delete quest/m1/bot-workflows-permission.md (moq-bot no longer pushes back-merges). Rewrite quest/m1/merge-queue-settings.md: ruleset 2420853 still has no merge_queue rule, so the squash queue stays pending, but the moq-bot pull_request bypass is dropped. Reword the back-merge note in quest/m0/broadcast-epoch/README.md for the manual pre-release merge.

Ordering

Gate cleared: back-merge #5176 merged at 2026-10-10T05:33Z, and this branch now includes it (main merged in).

The backport removing release's copy of the workflow is #5180, against release. Until it lands, a push to release still opens a back-merge PR that nothing lands; close it, or fold it into the pre-release merge.

Impact

• No public API or wire change. CI and process only.

Alternatives

• Keep the back-merge and finish the bot bypass and workflows permission: rejected by the maintainer.

Follow-ups

• quest/m1/merge-queue-settings.md: the maintainer still enables the squash queue on main.

(Written by Claude Opus 5.5)

🤖 Generated with Claude Code

[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 2026-10-10T12:31:29.467830Z	a9db60d	Draft marked ready

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No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

• Configuration used: Organization UI
• Review profile: CHILL
• Plan: Advanced
• Run ID: c378f46c-7110-4eff-a2cc-d473332ac630

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📥 Commits

Reviewing files that changed from the base of the PR and between fb0e34d and a9db60d.

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📒 Files selected for processing (10)

• .github/justfile
• .github/workflows/alert.yml
• .github/workflows/back-merge.yml
• .github/workflows/check.yml
• CONTRIBUTING.md
• quest/m0/broadcast-epoch/README.md
• quest/m1/README.md
• quest/m1/bot-workflows-permission.md
• quest/m1/merge-queue-settings.md
• sh/gh/back-merge.sh

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💤 Files with no reviewable changes (6)

• .github/justfile
• .github/workflows/back-merge.yml
• .github/workflows/check.yml
• .github/workflows/alert.yml
• sh/gh/back-merge.sh
• quest/m1/bot-workflows-permission.md

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Included review availability: This review used your included allowance. Your plan provides up to 4 included reviews per hour; 0 remain after this review.

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Walkthrough

The pull request removes the automated release-to-main back-merge script, recipe, and workflows. Contributor guidance now describes a maintainer-triggered, non-squashed merge before a minor or breaking release. Quest documentation updates the squash merge queue requirements and removes the bot-workflow permission quest.

Priority: ➖ Normal

Merge Risk: ⚪ Minimal · up to a9db6

The change replaces back-merge automation with a documented manual merge before minor or breaking releases. No established issue prevents merging.

Pre-merge checks | 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check		The title clearly and concisely identifies the main change: removing the automatic release back-merge process.
Description check		The description is directly related to the changeset and explains the problem, implementation, release process, impact, and follow-up work.
Docstring Coverage		No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

✨ Simplify code

• Commit to this branch
• Create a new PR

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• Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

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[kixelated]

Merge summary:

• Gate cleared: back-merge chore: merge release into main #5176 merged at 2026-10-10T05:33Z. main (including chore: merge release into main #5176) was merged into this branch; no conflicts, no back-merge references left in the tree, quest check passes.
• Review: Codex gave a thumbs-up on head a9db60dce701ed4f4ff1cde039a4ecd5fecefcc1; CodeRabbit reported no actionable comments.
• Check, Test, Windows, and macOS pass on that head.
• Squash-merging into main. The backport ci: remove the automatic release back-merge (backport #5179) #5180 removes release's copy of the workflow.

(Written by Claude Opus 5.5)