Add benchmark rate-limit bypass flag

[shaiananvari8]

Summary

Adds an explicit opt-in benchmark rate-limit bypass mode for tools/benchmark.py so load-test runs can request operator-approved bypass behavior without changing default benchmark traffic.

/claim #1

Changes

• Added global --bypass-rate-limit and --bypass-rate-limit-header CLI options.
• Propagated a documented X-ZeroEye-Benchmark-Bypass-Rate-Limit: true request header through latency, throughput, stress, soak, and spike workers when the bypass flag is enabled.
• Added warning output explaining that the target service/gateway must explicitly trust the bypass header.
• Included bypass metadata in printed results and JSON output.
• Documented operator usage in docs/OPERATIONS.md.
• Added tools/validate_benchmark_rate_limit_bypass.py for focused local validation.
• Swapped benchmark result separators to ASCII dashes so the tool completes in a default Windows console.

Testing

• python -m py_compile tools/benchmark.py tools/validate_benchmark_rate_limit_bypass.py passed using the bundled Python runtime.
• python tools/validate_benchmark_rate_limit_bypass.py passed.
• python tools/benchmark.py --endpoint http://127.0.0.1:9/health --bypass-rate-limit --concurrency 1 --timeout 0.1 latency --requests 1 completed and showed the bypass header request path. The endpoint was intentionally closed, so the single request failed as expected while the CLI completed successfully.
• git diff --check passed with only Git's Windows line-ending normalization warnings.
• python build.py -m backend was run with a workspace-local home so diagnostic packaging could complete. The backend module failed locally because cargo is not installed in this Windows environment, and the generated diagnostic artifacts are committed: diagnostic/build-94e0fb08.json and diagnostic/build-94e0fb08.logd.

Checklist

• Relevant modules affected by these changes build locally
• Tests pass locally
• Diagnostic build log is committed in this PR
• Documentation has been updated, if applicable
• Configuration or schema changes are documented, if applicable
• No generated build artifacts are committed, except the required diagnostic build log
• Changes are scoped to the PR purpose and avoid unrelated cleanup
• Security, privacy, and error-handling implications have been considered

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• I would like to request that my diagnostic build log is removed before merging

LLM assistance disclosure: implemented with OpenAI Codex assistance and manually reviewed before submission.