added why.md for the environments

[yogesh1801]

Description

This PR addresses Issue #22 by adding dedicated WHY.md files to each benchmark directory and linking them from the root README. These files explain why each benchmark matters and how it fits into the broader vision of system intelligence, following the pattern established in PR #21.

Changes

• Added WHY.md to System Exam Benchmark
• Added WHY.md to System Lab Benchmark
• Added WHY.md to System Artifact Benchmark
• Added WHY.md to System Modeling Benchmark
• Added WHY.md to Cache Algorithm Benchmark
• Updated root README.md to add WHY links next to each benchmark entry in the benchmark list
• Added Cache Algorithm Benchmark to the root README benchmark list (was previously missing)

Testing

• Verified all 5 WHY.md files exist in their respective benchmark directories
• Confirmed all WHY.md links in root README.md point to correct file paths
• Reviewed each WHY.md for consistency with benchmark READMEs and overall system intelligence vision
• Validated markdown formatting renders correctly

Checklist

• Tests pass locally (documentation-only changes)
• Code follows project style guidelines
• Documentation updated (this PR is documentation enhancement)

[bastoica]

I'm a bit confused as why you added a new WHY.md for arteval_bench. Is this simply the existing file or did you make any edits? Thanks!

[yogesh1801]

Hi @bastoica sorry for the confusion the arteval benchmark file is same, it is error from my side that it looks like a new file in commit, but it is the same
I have fixed the issue in the next commit

[bastoica]

sounds good, thanks @yogesh1801

[xuafeng]

@tareknaser can you help review if the new WHY.md make sense to you?

[xuafeng]

@Qian-Cheng-nju can you help review if the new WHY.md of SysMoBench works for you? Welcome any comments.

[Qian-Cheng-nju]

@Qian-Cheng-nju can you help review if the new WHY.md of SysMoBench works for you? Welcome any comments.

We recently added the ringbuffer module from Asterinas and ZooKeeper, so I updated the description of the number and types of systems. Everything looks good to me now. Thank you very much for such a detailed document!