<!-- TIER:1 -- Configuring Topics (Event Streams) A topic is a named, durable message channel . Publishers append messages; every listener receives all of them, reading from its own position at its own pace; and a message stays readable until the topic's retention window ends, whether or not anything read it. A topic decouples the flow that produces an event from the flows that consume it: add a consumer without touching the producer, pause one consumer while the others carry on, and let it catch up from where it stopped. A topic is an account resource that lives in one environment, outside a…