Add attributes needed by server to propagate control tasks to worker (#711)

<!-- Describe what has changed in this PR -->
**What changed?**

Added worker_control_task_queue to poll requests:
- PollActivityTaskQueueRequest
- PollWorkflowTaskQueueRequest
Note: worker_instance_key was already added to these requests in #686.

Added worker_instance_key and worker_control_task_queue to:
- RespondWorkflowTaskCompletedRequest: This API is used to eagerly fetch
activity.

<!-- Tell your future self why have you made these changes -->
**Why?**
To enable server to send control tasks to worker. Each worker provides a
worker_control_task_queue (a dedicated per-worker Nexus task queue) so
the server can send control tasks directly to it.

Example flow:
- User cancels a workflow.
- Server sends activity cancellation tasks to all workers that could be
processing activities belonging to that workflow.
- Worker will receive the cancellation message even when activity
heartbeat is not enabled.

<!-- Are there any breaking changes on binary or code level? -->
Breaking changes: None
[Server PR](temporalio/temporal#9231)

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Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: rkannan82