[engine-failure] PROJ-319-quantifying-the-impact-of-data-artifacts @ tasks: RuntimeError

Automated report (spec 023 / FR-016) — an unexpected engine failure occurred while processing **PROJ-319-quantifying-the-impact-of-data-artifacts** at stage `tasks`.

```
RuntimeError: LLMReviewer[coverage]: 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: coverage\nreviewer_kind: llm\nstage: tasked\nartifact_path: projects/PROJ-319-quantifying-the-impact-of-data-artifacts/specs/001-quantifying-the-impact-of-data-artifacts/tasks.'
```

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 PROJ-319 and trace the `LLMReviewer[coverage]` handling at the `tasks` stage, using the referenced review artifact path as the entry point. Determine why a truncated or contentless frontmatter review reaches acceptance handling; done means the engine no longer raises this failure and the normal retry can recover without a project-state change.

Written by the indexing model from the issue text.