[SigureMo]

Motivation

Native GitHub stacks currently look like unrelated PRs in gh-llm. For a middle layer, that hides its dependencies, confuses the direct diff base with the stack's merge target, and offers ordinary merge commands that do not handle native stack merging.

Changes

• Add a default stack summary and pr view --show stack, showing bottom-to-top membership, the current layer, target branch, and each member's draft/review/merge/CI state. Metadata-only views remain lightweight; stack entries are paginated.
• Show the merge scope from the first unmerged layer through the selected PR, explain blockers, and link to GitHub's native merge controls. Missing metadata or rules never imply merge readiness.
• Paginate head checks, distinguish workflows/runs, and retain the latest reported run per workflow/event. Read the stack target's classic protection and rulesets to label required checks and display missing contexts as EXPECTED, including app identity matching.
• Fix pr checks --all for closed and merged PRs. Historical checks do not apply today's branch requirements.
• Annotate PR-local diff/review scope and include base-branch changes in the timeline. Document schema fallback and API limitations.

Cumulative stack diffs and historical stack join/leave reconstruction remain outside this change; the latter's historical stack IDs are not reliably exposed by the API. No gh-stack installation or local stack state is required.

Validation

• uv run pytest -q: 128 passed, including 22 new stack/check regression cases.
• Ruff lint/format, ty check --error-on-warning, Prettier, and git diff --check passed.
• Live read-only checks against yutto #825: merged 3-layer stack with deleted branches and historical head checks.

^{This PR is co-authored with @codex (gpt-6-astra xhigh)}

[chatgpt-codex-connector]

To use Codex here, create an environment for this repo.

[SigureMo]

@codex review

[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 2026-09-30T16:06:09.278702Z	4f0017e	Manual request

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review" or "@codex security review".

Codex reacts with 👀 while any review is running, comments if it has suggestions, and reacts with 👍 once all reviews finish with no findings.

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. More of your lovely PRs please.

Reviewed commit: 4f0017ef06

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".