Investigate if heartbeat can be implemented

[nicholasgriffintn]

In SQS Consumer we have a heartbeat functionality that extends the visibility timeout every X seconds:

https://github.com/bbc/sqs-consumer/blob/main/src/consumer.ts#L339

It doesn't seem like it is currently possible to do the same with Cloudflare Queues, however, it is expected that this will be an important feature to users.