Revert "[V1] Exception Handling when Loading KV Cache from Remote Store"

[KuntaiDu]

Reverts #21534

This PR introduces fault tolerance to KV cache connector, which is very important feature to have. That said, I think this PR should be reverted because this PR, though has less core change, still contains some compatibility issue and need more feedbacks from community.

This PR is a consensus decision from #21534 .

[github-actions]

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[gemini-code-assist]

Code Review

This pull request reverts the "Exception Handling when Loading KV Cache from Remote Store" feature due to compatibility issues. The changes correctly remove the RandomDropConnector test utility and all associated logic for fault-tolerant KV cache loading from the scheduler, workers, and various data structures.

My review of the changes confirms that the revert appears to be clean and complete. I did not find any remaining artifacts or new issues introduced by this change. This should effectively address the compatibility concerns mentioned in the pull request description.

[njhill]

Thanks @KuntaiDu.

I agree this is a very high priority feature but we should take into account the overlapping existing work and make sure the right people have had a chance to comment.