feat(client): add TaskProducer

[bmckerry]

Ticket: https://linear.app/getsentry/issue/STREAM-950/create-the-taskproducer-abstraction-in-taskworker-client

This PR adds a TaskProducer class to the taskworker client. It works by taking an arroyo producer as argument, and when .produce() is called it tracks the producer future rather than returning it to the user.

Previously we talked about allowing the TaskProducer to use any producer internally (not just an arroyo one), but taskbroker_client already depends on arroyo and it'd be hard to get the typing to work otherwise (since arroyo producers can return SimpleProducerFuture, which needs to be handled differently from regular concurrent.future.Future's).

[cursor]

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