[engine-failure] PROJ-211-predicting-gene-expression-from-chromati @ tasks: RuntimeError

Automated report (spec 023 / FR-016) — an unexpected engine failure occurred while processing **PROJ-211-predicting-gene-expression-from-chromati** at stage `tasks`.

```
RuntimeError: LLMReviewer[executability]: review frontmatter has neither `verdict:` nor `concerns:`/`action_items:` — a contentless/truncated review MUST NOT count as acceptance (false-convergence guard). First 200 chars: '```yaml\n---\nreviewer_name: rq_validity\nreviewer_kind: llm\nstage: fleshed_out_complete\nartifact_path: projects/PROJ-211-predicting-gene-expression-from-chromati/specs/001-predicting-gene-expression-fro'
```

The project remains schedulable; it will retry on its normal cadence and recover once the underlying defect is fixed. Closing this issue does not require any project-state change.

Start with the automated report for spec 023 / FR-016 and the `LLMReviewer[executability]` failure, then trace how the review frontmatter is processed at the `tasks` stage. Done means a review lacking `verdict:` and `concerns:`/`action_items:` cannot count as acceptance, while the normal retry remains schedulable.

Written by the indexing model from the issue text.