[13.x] Throw ManagedQueueNotFoundException when a managed queue is missing (#60275)

* Throw ManagedQueueNotFoundException with queue name for missing managed queues

Wraps AWS.SimpleQueueService.NonExistentQueue errors at the SQS client
handler stack so every managed queue operation surfaces a clear message
including the queue name, instead of the vague AWS error.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* Reword ManagedQueueNotFoundException message

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* Use expectException/expectExceptionMessage in managed queue not found test

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>