[aw] CI Outer-Loop Failure Scanner failed

### Workflow Failure

**Workflow:** [CI Outer-Loop Failure Scanner](https://github.com/dotnet/runtime/blob/main/.github/workflows/ci-failure-scan.md)
**Branch:** main
**Run:** https://github.com/dotnet/runtime/actions/runs/32138653968

> [!WARNING]
> **Engine Failure**: The `copilot` engine terminated unexpectedly.

**Last agent output:**
```
Changes +0 -0
Duration 4s
Resume copilot --resume=b2bd9405-1f1a-4ede-be40-20fe75aefd7b
● Request failed (transient_auth_error). Retrying...
● Request failed (transient_auth_error). Retrying...
Authentication failed with provider at http://172.30.0.30:10002 (HTTP 401).
Check your COPILOT_PROVIDER_API_KEY or COPILOT_PROVIDER_BEARER_TOKEN.
Changes +0 -0
Duration 4s
Resume copilot --resume=a46feace-21d3-4f61-8eff-95c294c37c1a
```

### Action Required

**Assign this issue to an agent** to debug and fix the issue.

Debug with any coding agent

Use this prompt with any coding agent (GitHub Copilot, Claude, Gemini, etc.):

````
Debug the agentic workflow failure using https://raw.githubusercontent.com/github/gh-aw/main/debug.md

The failed workflow run is at https://github.com/dotnet/runtime/actions/runs/32138653968
````

Manually invoke the agent

Debug this workflow failure using your favorite Agent CLI and the `agentic-workflows` prompt.

- Start your agent
- Load the `agentic-workflows` skill from `.github/skills/agentic-workflows/SKILL.md` or
- Type `debug the agentic workflow ci-failure-scan failure in https://github.com/dotnet/runtime/actions/runs/32138653968`

> [!TIP]
>
> Stop reporting this workflow as a failure
>
> To stop a workflow from creating failure issues, set `report-failure-as-issue: false` in its frontmatter:
> ```yaml
> safe-outputs:
> report-failure-as-issue: false
> ```
>
>

> Generated from [CI Outer-Loop Failure Scanner](https://github.com/dotnet/runtime/actions/runs/32138653968) · [◷](https://github.com/search?q=repo%3Adotnet%2Fruntime+is%3Aissue+%22gh-aw-workflow-id%3A+ci-failure-scan%22&type=issues)

Start with the failed run linked in the issue and read .github/workflows/ci-failure-scan.md, then follow the debugging guidance in debug.md and .github/skills/agentic-workflows/SKILL.md. Determine why the copilot engine received a 401 from its provider and verify the scanner completes successfully without creating another failure issue.

Written by the indexing model from the issue text.