[engine-failure] PROJ-864-llmxive-follow-up-extending-improved-lar @ tasks: RuntimeError

Automated report (spec 023 / FR-016) — an unexpected engine failure occurred while processing **PROJ-864-llmxive-follow-up-extending-improved-lar** 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: ordering\nreviewer_kind: llm\nstage: tasks_complete\nartifact_path: projects/PROJ-864-llmxive-follow-up-extending-improved-lar/specs/001-llmxive-follow-up-extending-improved-la'
```

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 tracing the engine-failure report at the `tasks` stage and the `LLMReviewer[ordering]` handling of the truncated review frontmatter shown in the error. Confirm that a review without `verdict:` or `concerns:`/`action_items:` cannot count as acceptance, then verify that the normal retry can recover without a project-state change.

Written by the indexing model from the issue text.