Consider CLS-compliancy

### Overview

Currently we have (among others) following properties set in our `Directory.Build.props`:
```xml
AllEnabledByDefault
true

```
Due to [`CA1014`](https://learn.microsoft.com/en-us/dotnet/fundamentals/code-analysis/quality-rules/ca1014), we've marked our assemblies with
```csharp
[assembly: CLSCompliant(true)]
```
This we do not want to change.

Previously we've made use of code generation and marked our viewmodels with the `ObservableObjectAttribute`. However, with the newest version, this triggers the analyzer `MVVMTK0033` ("The type XXX is using the [ObservableObject] attribute while having no base type, and it should instead inherit from ObservableObject").

If we follow this advice and inherit from `ObservableObject`, the analyzer [`CS3009`](https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/compiler-messages/cs3009) triggers because even tho the class is technically compliant with the common language specification, it is not marked as such.

### API breakdown

I would like to propose marking either the whole assembly as `CLSCompliant` or (at least) marking `ObservableObject` as such.

### Usage example

```csharp
public sealed partial class MyViewModel : ObservableObject {
...
}
```

### Breaking change?

No

### Alternatives

```csharp
[ObservableObject]
#pragma warning disable MVVMTK0033
public sealed partial class MyViewModel {
#pragma warning restore MVVMTK0033
...
}
```

### Additional context

Thank you in advance for considering the inclusion of this.

### Help us help you

Yes, but only if others can assist