[engine-failure] PROJ-546-predicting-molecular-properties-from-qua @ tasks: RuntimeError

Automated report (spec 023 / FR-016) — an unexpected engine failure occurred while processing **PROJ-546-predicting-molecular-properties-from-qua** 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-546-predicting-molecular-properties-from-qua/specs/001-predicting-molecular-properties-from-qua/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 by locating LLMReviewer[coverage] and the review artifact under projects/PROJ-546-predicting-molecular-properties-from-qua/specs/001-predicting-molecular-properties-from-qua/tasks. Inspect why the tasks-stage frontmatter reached review without verdict, concerns, or action_items, then reproduce the retry; done means a contentless or truncated review cannot count as acceptance and normal recovery remains possible.

Written by the indexing model from the issue text.