Add Support for Keyed Services

[Chris-Wolfgang]

I am trying to use keyed services (https://learn.microsoft.com/en-us/dotnet/api/microsoft.extensions.dependencyinjection.servicecollectionserviceextensions.addkeyedsingleton?view=net-9.0-pp) but it appears that the current code supports it.

I'm using the following code

.ConfigureServices((_, serviceCollection) =>
{
	serviceCollection.AddKeyedSingleton<DbConnection>("Database1", new SqlConnection(...));
	serviceCollection.AddKeyedSingleton<DbConnection>("Database2", new SqlConnection(...));
})

and

internal void OnExecute
(
	[FromKeyedServices("Database1")] DbConnection connection1,
	[FromKeyedServices("Database2")] DbConnection connection2,
)

I think the solution is to update the BindParameters method in ReflectionHelper.cs

else
{
	// Check for FromKeyedServicesAttribute
	var keyedAttr = methodParam.GetCustomAttribute<FromKeyedServicesAttribute>();
	if (keyedAttr != null)
	{
		if (command.AdditionalServices is not IKeyedServiceProvider keyedServiceProvider)
		{
			throw new InvalidOperationException("AdditionalServices does not support keyed service resolution.");
		}

		arguments[i] = keyedServiceProvider.GetKeyedService(methodParam.ParameterType, keyedAttr.Key)
					   ?? throw new InvalidOperationException($"No keyed service found for type {methodParam.ParameterType} and key '{keyedAttr.Key}'.");
	}
	else
	{
		var service = command.AdditionalServices?.GetService(methodParam.ParameterType);
		arguments[i] = service
					   ?? throw new InvalidOperationException(Strings.UnsupportedParameterTypeOnMethod(method.Name, methodParam));
	}
}