fix(review): report a withheld narrative honestly instead of as a provider failure

[JSONbored]

The bug (the last of today's review-reliability incidents)

JSONbored/loopover#9794 produced "AI review is unavailable for this PR head" on every run — including forced re-ticks, including after the beta.4 deploy — while its diagnostics said claude-code#0:parsed. The provider was fine every time.

The real path: the model reviewed scoring/proof code, found no blockers and no nits, so its entire output was the narrative — and an honest narrative about this project's own gate/scoring code says "score"/"ranking"/"reward" in every sentence. The per-sentence sanitizer withheld all of them, composeAdvisoryNotes returned null, and the orchestration's null-branch misattributed that to the provider, held the PR, and — the head being unchanged — reproduced identically on every re-run. A permanently wedged PR whose review succeeded every single time.

The fix

When the parse produced a narrative but nothing survived sanitization, publish a fixed, public-safe sentence instead of null — no model text, so the never-echo guarantee is untouched — worded by the review's real verdict:

• no raw blockers → "completed and found no blocking issues; narrative withheld (non-public project internals)"
• raw blockers all withheld → "raised blocking findings … withheld; a maintainer should read the private review record" — withheld blockers must never read as a clean result (pinned by an invariant test)

A truly empty parse (no assessment at all) still returns null, so a genuine provider failure keeps its accurate "unavailable" report.

One legacy test explicitly pinned the old null behavior — the exact behavior this incident traces to — and is updated with the incident reference.

Tests

286 pass in test/unit/ai-review.test.ts, including the #9794 regression (all-withheld clean review → honest note, hasPublicReviewAssessment true), the withheld-blockers invariant, and the true-provider-failure null case. tsc clean.

With this, every failure mode from today's investigation has a landed fix: cadence downgrade + false "skipped" bullet (#9800), restart-orphaned reviews (#9802), and this misattribution. Next image picks up all three.

[loopover-orb]

Important

🟨🟨🟨🟨🟨🟨🟨🟨🟨🟨🟨🟨

⏳ LoopOver is waiting…

LoopOver has seen this pull request and is waiting on CI checks to finish before reviewing it. This comment will update once the review runs.

_{🟩 Safe / merged · 🟦 Advisory · 🟨 Held for review · 🟥 Blocked / closed · 🟨 Waiting}

[superagent-security]

Superagent didn't find any vulnerabilities or security issues in this PR.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.51%. Comparing base (ace8d1a) to head (73430bd).
⚠️ Report is 5 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9806      +/-   ##
==========================================
- Coverage   90.33%   89.51%   -0.82%     
==========================================
  Files         918      918              
  Lines      113935   113938       +3     
  Branches    26974    26976       +2     
==========================================
- Hits       102925   101997     -928     
- Misses       9681    10850    +1169     
+ Partials     1329     1091     -238     

Flag	Coverage Δ
backend	94.09% <100.00%> (-1.48%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/services/ai-review.ts	96.95% <100.00%> (-0.11%)	⬇️

... and 3 files with indirect coverage changes