Exception thrown from a trigger and caught in the middleware has incorrect Source value

[SeanFeldman]

Description

When an exception is thrown from a function (ASB trigger) and is caught and handled in the custom middleware, the exception Source is set incorrectly to the middleware rather than the throwing function.

The source (1) is the namespace rather than the location where the exception was thrown, as indicated in the StackTrace (2)

Steps to reproduce

Function

public class AsbTrigger
{
    [Function("AsbTrigger")]
    public async Task Run([ServiceBusTrigger("myqueue", Connection = "AzureServiceBus")] ServiceBusReceivedMessage message, FunctionContext context)
    {
        var logger = context.GetLogger("AsbTrigger");
        
        logger.LogInformation("C# ServiceBus queue trigger function processed message: {MessageId}", message.MessageId);
        
        throw new Exception("boom!");
    }
}

Middleware

internal class ServiceBusMiddleware(IAzureClientFactory<ServiceBusClient> azureClientFactory, ILogger<ServiceBusMiddleware> logger) : IFunctionsWorkerMiddleware
{
    private readonly ServiceBusClient asbClient = azureClientFactory.CreateClient("default");

    public async Task Invoke(FunctionContext context, FunctionExecutionDelegate next)
    {
        try
        {
            await next(context);
        }
        catch (Exception exception)
        {
               logger.LogDebug("Failed at {Source}", exception.Source);
               throw;
        }
    }
}

[SeanFeldman]

This is aligned with normal exception handling. I got confused by the previous implementation where AggregateException has the source set (#993).