public synchronized CompletableFuture<T> settled() {
		if (settledPromise == null) {
			settledPromise = new CompletableFuture<>();
		}
		return settledPromise;
	}
Receive the next settled event

<p>
The returned future completes <em>after</em> all registered listeners have been invoked.

@return a future which completes with the value of the next settled event
Ghidra/Framework/Generic/src/main/java/ghidra/async/AsyncDebouncer.java