[CI Failure] Templates-NewUpAndBuildStandaloneTemplateTests (macos-latest) 'Run nuget dependent tests' step fails with generic exit code 3, unrelated to PR changes

## Build Information

Build: https://github.com/microsoft/aspire/actions/runs/34268996559
Build error leg or test failing: Tests / Run VS Code extension E2E tests / VS Code extension E2E (Windows, dynamic-debug-configuration) / `Aspire.Templates.Tests.NewUpAndBuildStandaloneTemplateTests`
Pull request: #19985

## Error Message

```
Process completed with exit code 3. (Run nuget dependent tests (Linux/macOS) step failed; job logs unavailable: 'Failed to fetch logs for job'). No TRX test failures extracted. PR only modifies .github/workflows/organization-funded-copilot-reviews.yml, docs, and Infrastructure.Tests workflow-script tests, unrelated to templates.
```

## Description

Templates-NewUpAndBuildStandaloneTemplateTests (macos-latest) 'Run nuget dependent tests' step fails with generic exit code 3, unrelated to PR changes

**Type**: flaky-test

## Occurrences

| Date | Build | Job | PR |
|------|-------|-----|----|
| 2026-09-08 | [34268996559](https://github.com/microsoft/aspire/actions/runs/34268996559) | Tests / Run VS Code extension E2E tests / VS Code extension E2E (Windows, dynamic-debug-configuration) | #19985 |

Start with build 34268996559 and the Templates-NewUpAndBuildStandaloneTemplateTests failure in the “Run nuget dependent tests” step; the job logs are currently unavailable. Inspect the related workflow and Infrastructure.Tests workflow-script tests to determine why macos-latest exits with code 3. Done means the flaky failure has an identified cause and the affected CI step completes reliably.

Written by the indexing model from the issue text.