Using a grain before WebApplication.Run throws NRE

```cs
using Orleans.Runtime;

var builder = WebApplication.CreateBuilder(args);
builder.Host.UseOrleans(siloBuilder =>
{
siloBuilder.UseLocalhostClustering();
siloBuilder.AddMemoryGrainStorage("tests");
});
var app = builder.Build();
await app.Services
.GetRequiredService().GetGrain(Guid.NewGuid())
.Test();

interface ITestGrain : IGrainWithGuidKey { Task Test(); }
class Test { }

class TestGrain : Grain, ITestGrain
{
private readonly IPersistentState _state;

public TestGrain([PersistentState(stateName: "test", storageName: "tests")] IPersistentState state)
{
_state = state;
}

public Task Test() => Task.CompletedTask;
}
```

I understand from https://github.com/dotnet/orleans/issues/8240 that the silo hosted service needs to be initialized before using Orleans but what do you think about throwing a more explicit exception such as "Orleans was not initialized...".

Start with the supplied WebApplication reproduction, focusing on the GetRequiredService() call made before WebApplication.Run. Trace Orleans initialization at that entry point and verify that using a grain before initialization produces an explicit Orleans-not-initialized exception rather than an NRE.

Written by the indexing model from the issue text.