perf: Benchmark

- [ ] Benchmark performance of 1 node
- [ ] Benchmark performance of multiple node
- [ ] Benchmark relay latency

The issue mentions benchmarking performance for single and multiple nodes, and relay latency. Look for existing benchmarks in the codebase, likely in a `benches/` directory or using Criterion. Determine how to set up a test node, measure throughput/latency, and run comparisons. The 'done' state is a set of benchmark results and possibly a report.

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