[engine-failure] PROJ-259-predicting-plant-disease-resistance-from @ tasks: PermanentBackendError

Automated report (spec 023 / FR-016) — an unexpected engine failure occurred while processing **PROJ-259-predicting-plant-disease-resistance-from** at stage `tasks`.

```
PermanentBackendError: no available server
```

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 automated report for spec 023 / FR-016 at the `tasks` stage and investigate why it reports `PermanentBackendError: no available server`. Reproduce the failure through the normal project cadence; done means the task completes without the permanent engine failure and no project-state change is required.

Written by the indexing model from the issue text.