Feature: Client receives asynchronous `ChunkReservationExpired` not actionable from library

https://github.com/channable/opsqueue/blob/bd0a42e7f45ccd2750071e3dd3cd9bd4dda4fd25/opsqueue/src/consumer/client.rs#L293-L295

I would expect a local cancellation token that we can await to be informed we should stop processing the `Chunk`.

Start in opsqueue/src/consumer/client.rs at lines 293-295 and trace how ChunkReservationExpired is delivered to the client. Determine how an awaitable local cancellation token should signal that processing of the Chunk must stop, then verify the expiration path informs consumers as requested.

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