winget install github.copilot installs PowerShell even when PowerShell Preview is installed

### Describe the bug

When installing GitHub Copilot CLI with `winget`, running `winget install github.copilot` installs `microsoft.powershell` even when `microsoft.powershell.preview` with a newer version of PowerShell is installed and available.

### Affected version

1.0.44

### Steps to reproduce the behavior

1. Install PowerShell preview on Windows with `winget install Microsoft.PowerShell.Preview`
2. Install GitHub Copilot CLI with `winget install github.copilot`

### Expected behavior

The installer sees `Microsoft.PowerShell.Preview` and uses that, instead of also installing the GA `Microsoft.PowerShell`.

### Additional context

This is fundamentally an issue in the WinGet schema, which needs OR options.