Adding property using [ObservableProperty] breaks hot reload

### Describe the bug

Run application
Add viewmodel class and save changes (triggering hot reload) eg
```csharp
internal partial class MainViewModel : ObservableObject
{
}
```
Add properties and save changes (attempting to trigger hot reload) eg
```csharp
[ObservableProperty]
private int _count = 0;

[ObservableProperty]
private int _step = 1;
```
This raises a hot reload error

### Regression

_No response_

### Steps to reproduce

```text
see description
```

### Expected behavior

Hot reload should be successful

### Screenshots

_No response_

### IDE and version

VS 2022

### IDE version

_No response_

### Nuget packages

- [ ] CommunityToolkit.Common
- [ ] CommunityToolkit.Diagnostics
- [ ] CommunityToolkit.HighPerformance
- [ ] CommunityToolkit.Mvvm (aka MVVM Toolkit)

### Nuget package version(s)

8.2.2

### Additional context

_No response_

### Help us help you

No, just wanted to report this