[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/34175577268

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

**Last agent output:**
```
Check your COPILOT_PROVIDER_API_KEY or COPILOT_PROVIDER_BEARER_TOKEN.
Changes +0 -0
Duration 24m 14s
Tokens ↑ 1.1m (1.0m cached) • ↓ 6.7k
Resume copilot --resume=829da8b7-4b61-4c09-a48a-b55cf9bebd05
Authentication failed with provider at http://172.30.0.30:10002 (HTTP 403).
Check your COPILOT_PROVIDER_API_KEY or COPILOT_PROVIDER_BEARER_TOKEN.
Changes +0 -0
Duration 0s
Resume copilot --resume=0d5648d9-c449-470f-a138-ca4ae42e0d21
```

### 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/34175577268
````

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/34175577268`

> [!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/34175577268) · 990.4 AIC · [◷](https://github.com/search?q=repo%3Adotnet%2Fruntime+is%3Aissue+%22gh-aw-workflow-id%3A+ci-failure-scan%22&type=issues)

Start with .github/workflows/ci-failure-scan.md and the linked workflow run, then read .github/skills/agentic-workflows/SKILL.md for the expected debugging process. Trace the Copilot provider authentication failure and verify that the CI Outer-Loop Failure Scanner completes successfully without the HTTP 403 engine error.

Written by the indexing model from the issue text.