fix: ensure range requests in txn are executed on all cluster members

[kairosci]

Summary

• Fix data inconsistency issue Specifying a revision for a range request in a transaction may cause data inconsistency #18667 where specifying a revision for a range request in a transaction may cause data inconsistency across cluster members
• Removed the removeNeedlessRangeReqs function that was incorrectly removing range requests from txn operations on some cluster members

Root Cause

When a client makes a txn with a range request (e.g., get key --rev=X), if the revision has been compacted:

• On members where the range request is executed, the txn fails with ErrCompacted
• On members where the range request was removed by removeNeedlessRangeReqs, the txn proceeds and executes the write operations (put/delete)

This leads to data inconsistency across cluster members.

Solution

Remove the optimization that removes range requests from read-only txns. This ensures all cluster members execute the same validation and maintain consistent data.

Testing

• All existing tests pass
• The fix ensures that when a txn with a range request fails (e.g., due to ErrCompacted), it fails consistently across all cluster members

[k8s-ci-robot]

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This pull-request has been approved by: kairosci
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[k8s-ci-robot]

Hi @kairosci. Thanks for your PR.

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