feat: implement dataset-agnostic router reasoning benchmark

[rootfs]

What type of PR is this?

The current router reason bench is based on MMLU-Pro. This new bench tests more cases with more datasets.

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #

Release Notes: Yes/No

[github-actions]

👥 vLLM Semantic Team Notification

The following members have been identified for the changed files in this PR and have been automatically assigned:

📁 bench

Owners: @yuezhu1, @Xunzhuo
Files changed:

• bench/LICENSE
• bench/MANIFEST.in
• bench/README.md
• bench/benchmark_comparison.sh
• bench/build_and_test.sh
• bench/comprehensive_bench.sh
• bench/pyproject.toml
• bench/requirements.txt
• bench/setup.py
• bench/vllm_semantic_router_bench/__init__.py
• bench/vllm_semantic_router_bench/cli.py
• bench/vllm_semantic_router_bench/dataset_factory.py
• bench/vllm_semantic_router_bench/dataset_implementations/__init__.py
• bench/vllm_semantic_router_bench/dataset_implementations/arc_dataset.py
• bench/vllm_semantic_router_bench/dataset_implementations/commonsenseqa_dataset.py
• bench/vllm_semantic_router_bench/dataset_implementations/gpqa_dataset.py
• bench/vllm_semantic_router_bench/dataset_implementations/hellaswag_dataset.py
• bench/vllm_semantic_router_bench/dataset_implementations/mmlu_dataset.py
• bench/vllm_semantic_router_bench/dataset_implementations/truthfulqa_dataset.py
• bench/vllm_semantic_router_bench/dataset_interface.py
• bench/vllm_semantic_router_bench/router_reason_bench_multi_dataset.py
• bench/router_reason_bench.py
• bench/vllm_semantic_router_bench/bench_plot.py

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🎉 Thanks for your contributions!

This comment was automatically generated based on the OWNER files in the repository.

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