[engine-failure] PROJ-269-assessing-the-impact-of-data-augmentatio @ tasks: PermanentBackendError

Automated report (spec 023 / FR-016) — an unexpected engine failure occurred while processing **PROJ-269-assessing-the-impact-of-data-augmentatio** 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.

The report identifies the tasks stage and the error PermanentBackendError: no available server, but names no file, test, or entry point. Start by tracing how tasks-stage engine failures and server availability are handled, then reproduce the failure and determine what should recover it without changing project state.

Written by the indexing model from the issue text.