Emit outcomes in Kafka delivery callback

[jjbayer]

1. For any data type that the delivery() callback in the Kafka producer gets an error for, we should create an outcome. This requires being able to map the topic string to a data type, and derive the outcome quantity from the message somehow.
2. For spans, we emit Accepted outcomes before we produce to Kafka, but producing to Kafka might still fail asynchronously. We should instead emit the outcome from the success branch of the delivery callback (see https://github.com/getsentry/relay/pull/3315#discussion_r1537484263).

[olksdr]

Still need to check it that's possible.