Performance: Baseline Benchmark Suite and Regression Guard

[AnishMulay]

Summary

Create reproducible benchmarks for store/read under varying sizes, replication factors, and network conditions.

Scope

• Go benchmarks and standalone load generator.
• Output JUnit/CSV, publish trends in CI.
• Scenarios: single large file, many small files, mixed workloads.

Acceptance Criteria

• CI job runs and stores artifacts.
• Detects >10% regressions and flags PRs.

Notes

Later integrate with pprof and flamegraphs.