work: h051-054-failed-ci-bounded-diagnosis-surface

[ExatronOmega]

Summary

• Signposter handoff for issue H051-054 — Failed CI bounded diagnosis surface #584.
• Source branch: work/issue-584-h051-054-failed-ci-bounded-diagnosis-surface
• Base branch: main

Changed files

• src/signposter/pr.py
• tests/test_pr.py

Safety notes

• Generated by Signposter PR planning surface.
• No merge or issue close is implied by this PR.
• Issue should remain open until explicit integration/close policy.

Related issue: #584

[AlphaExatron]

Signposter reviewer gate: APPROVE

Confidence: 0.9
Risk: medium
Scope match: yes
CI considered: yes
Merge recommendation: yes
Automerge eligible: no

Findings:

• Scope is limited to src/signposter/pr.py and tests/test_pr.py.
• The failed-CI diagnosis helper is read-only and does not poll or mutate GitHub.
• Failing check summaries are bounded and use existing redaction behavior before operator-facing output.
• Tests cover bounded/redacted failing evidence, missing failing evidence, and passing CI.

Summary:
Reviewer approved this change.

No merge or issue close is implied by this review.