### Problem
The legacy PR Azure Pipelines definition still used Windows / VS 2019
pool images in `azure-pipelines-pr.yml`. Those image references need to
move to VS 2022 before the 2019 images are retired.

### Solution
- **Windows PR job image update**
- Replaced the public pool image from `1es-windows-2019-open` to
`1es-windows-2022-open`.
- Replaced the internal pool override from `windows.vs2019.amd64` to
`windows.vs2022.amd64`.

- **Reference cleanup**
- Searched repository pipeline YAML for other `vs2019` / Windows 2019
image references and found no additional matches requiring changes.

```yaml
pool:
  name: $(DncEngPublicBuildPool)
  vmImage: 1es-windows-2022-open
```

### Checks:
- [ ] Added unit tests