fix: Use DATASETS env var for arvo_meta paths instead of pk…

[kyle-deprow]

…g_resources

Fixes critical FileNotFoundError that breaks the benchmark during agent evaluation post fix when loading ground truth json patches by using DATASETS env variable to locate arvo_meta files in datasets/autopatch/arvo_meta/ instead of hardcoded benchmark/arvo_meta/ path return via pkg_resources.

• Add get_arvo_meta_path() helper that reads DATASETS env var
• Raises RuntimeError with clear message if DATASETS not set
• Update all arvo_meta path references to use new helper

[meta-codesync]

@dwjsong has imported this pull request. If you are a Meta employee, you can view this in D87653674.

[lshariprasad]

Solution Implemented
The fix introduces environment variable-based path resolution instead of relying on hardcoded paths.
Key Changes:
Added get_arvo_meta_path() helper function that reads the DATASETS environment variable to dynamically locate the correct arvo_meta file paths.
Error handling that raises a RuntimeError with a clear error message if the DATASETS environment variable is not set.
Updated all arvo_meta path references throughout the codebase to use the new helper function.

Code Changes
The pull request modifies 2 files with +20 −13 net changes (20 additions, 13 deletions).

Quality Assurance
All checks have passed successfully.
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Rationale
This approach provides several benefits:
Flexibility: The DATASETS environment variable allows runtime configuration of file paths rather than compile-time hardcoding.
Robustness: Clear error messages help developers diagnose configuration issues immediately.
Maintainability: Centralizing path resolution in a helper function makes the codebase easier to maintain and modify.
Portability: Different deployment environments can set the DATASETS variable appropriately.

Status
The pull request is ready for merge, having passed all required checks and obtained the necessary contributor license agreement signature.