[engine-failure] PROJ-912-llmxive-follow-up-extending-audio-intera @ tasks: RuntimeError

Automated report (spec 023 / FR-016) — an unexpected engine failure occurred while processing **PROJ-912-llmxive-follow-up-extending-audio-intera** 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-912-llmxive-follow-up-extending-audio-intera/specs/001-llmxive-follow-up-extending-audio-intera/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 spec 023 / FR-016 and trace the LLMReviewer[coverage] handling at the `tasks` stage for projects/PROJ-912-llmxive-follow-up-extending-audio-intera/specs/001-llmxive-follow-up-extending-audio-intera/tasks. Reproduce the retry if possible and inspect how review frontmatter is parsed; done means a truncated review lacking `verdict:`, `concerns:`, or `action_items:` raises the intended guard without counting as acceptance.

Written by the indexing model from the issue text.