[Bug] IJSUnmarshalledRuntime is obsolote in .NET 7

[Ksdmg]

I have a .NET 7 project running blazor server side. When initializing the JSRuntime, an exception is thrown:

await FFmpegFactory.Init(Runtime); // throws System.InvalidCastException: 'Unable to cast object of type 'Microsoft.AspNetCore.Components.Server.Circuits.RemoteJSRuntime' to type 'Microsoft.JSInterop.IJSUnmarshalledRuntime'.'

I found this -> https://github.com/dotnet/AspNetCore.Docs/blob/main/aspnetcore/blazor/javascript-interoperability/import-export-interop.md#obsolete-javascript-interop-api

[BigBang1112]

It also seems to be completely removed in .NET 9.

[sps014]

I will mostly rewrite the current js interop code after .NET 9 RC2 release, hopefully they have some news regarding .net wasm threads.

[BigBang1112]

I've been roughly following where the new Blazor goes and I think they delayed multithreading once again (like they delay half of the features as usual), and looking deeper it is indeed the reality: https://github.com/dotnet/aspnetcore/issues/17730#issuecomment-2059602250 (which is funny when I look into the readme history)

[sps014]

Closing this as I have removed IJSUnmarshalled API from source.