Release internal algorithmic test cases

[joyemang33]

Summary

Release the formerly private algorithmic test cases into the public repository.
Update batch evaluation to use the released public problem data by default, without requiring access to the internal repository.
Extend the algorithmic judge to include complete extra testdata pairs that are present beyond the historical configured case count.
Update README messaging to announce that full local, batch, and agent-based evaluation is now possible without internal repository access.

Type of Change

• New research problem
• New algorithmic problem
• Bug fix
• Documentation update
• Other:

Testing

Checklist

• Code follows the project structure and conventions
• Self-review completed
• Documentation updated (if applicable)

CI Validation (for new problems)

When adding new problems, CI will automatically validate that your reference solution achieves score > 0.

• Algorithmic problems: Include reference.cpp in your problem directory
• Research problems: Include reference.py (or reference.cpp if language: cpp in config.yaml)