[engine-failure] PROJ-840-llmxive-follow-up-extending-agents-last @ tasks: RuntimeError

Automated report (spec 023 / FR-016) — an unexpected engine failure occurred while processing **PROJ-840-llmxive-follow-up-extending-agents-last** at stage `tasks`.

```
RuntimeError: LLMReviewer[ordering]: 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: dependency_ordering\nreviewer_kind: llm\nstage: tasks\nartifact_path: projects/PROJ-840-llmxive-follow-up-extending-agents-last/specs/001-llmxive-follow-up-extending-agents-las'
```

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-840 and inspect the review artifact under the mentioned `projects/PROJ-840-llmxive-follow-up-extending-agents-last/specs/001-llmxive-follow-up-extending-agents-las…` path. Trace the `tasks` stage and `LLMReviewer[ordering]` failure; done means a contentless or truncated review is not counted as acceptance and the project can recover on retry.

Written by the indexing model from the issue text.