refactor(cd): Test package locally before publishing to NuGet

[currantw]

Summary

Reorder the CD pipeline to test the package locally before publishing to NuGet, eliminating the risk of publishing a broken package. Also removes the temporary relist-package.yml workflow (no longer needed).

Issue Link

⚪ None

Features and Behaviour Changes

Before: build → publish → test (NuGet artifact) → unlist-if-failed

• Flaky test failures would unlist an already-published package, burning the version number and requiring manual re-listing.

After: build → test (local artifact) → publish

• Tests run against the .nupkg artifact via a local NuGet source. Publishing only happens if all tests pass. No version numbers are burned on test failures.

Implementation

• Moved the test job to depend on build-package-to-publish instead of publish.
• The test job now always uses package-artifact-name: package (the local .nupkg artifact).
• Moved publish to depend on test — it only runs after tests pass.
• Removed the Wait for package to be ready for download step (no longer needed since we test locally).
• Removed the remove-package-if-validation-fails job (no longer needed since we don't publish before testing).
• Removed .github/workflows/relist-package.yml (temporary workflow, no longer needed with this fix).

Limitations

• Tests no longer validate the package as installed from nuget.org. This is considered an acceptable tradeoff since the .nupkg content is identical and it allows us to avoid publishing the package before verifying it.

Testing

⚠️ After merging, need to manually run CD pipeline without publishing.

Related Issues

• chore(ci): Add workflow to re-list unlisted NuGet packages #400 — chore(ci): Add workflow to re-list unlisted NuGet packages (now removed)
• fix(ci): Add Content-Length header to NuGet re-list request #401 — fix(ci): Add Content-Length header to NuGet re-list request (now removed)

Checklist

• This Pull Request is related to one issue.
• Commit message has a detailed description of what changed and why.
• Tests are added or updated and all checks pass.
• CHANGELOG.md, README.md, DEVELOPER.md, and other documentation files are updated.
• Destination branch is correct - main or release
• Create merge commit if merging release branch into main, squash otherwise.