Route ListTransactions request

[rukai]

This PR implements routing for ListTransactions requests by applying the same routing logic to ListTransactions as we did for ListGroups in #1790

However, I found that while the java driver deduplicates entries in ListGroups responses it does not do the same for ListTransactions responses.

So I had to alter the logic in split_request_by_routing_to_all_brokers to avoid duplicates.
As a result ListGroups is actually more efficient as we better distribute the load across shotover instances by avoiding querying the same node twice.

The comment on split_request_by_routing_to_all_brokers explains the new logic pretty well:

/// Route broadcast requests to all brokers split across all shotover nodes.
/// That is, each shotover node in a rack will deterministically be assigned a portion of the rack to route the request to.
/// If a shotover node is the only node in its rack it will route to all kafka brokers in the rack.
/// When combined with a client that is routing this request to all shotover nodes, the request will reach each kafka broker exactly once.

[codspeed-hq]

CodSpeed Performance Report

Merging #1797 will not alter performance

_{Comparing rukai:list_transactions (fd59ddb) with main (f81fbdb)}

Summary

✅ 38 untouched benchmarks