[Fix] fix MathCanvas-Bench md5 & summarize_mathcanvas_results

[shiwk24]

Summary

Fixes two issues affecting MathCanvas-Bench usage and reporting.

Changes

• Dataset TSV / MD5: Update MathCanvas-Bench checksum in image_vqa.py so the local TSV matches the current file and avoids unnecessary re-download / mismatch warnings. The TSV contains one minor data update at index 165: the question image was redrawn in Python to improve the coordinate system rendering. This does not affect the problem content or solving.
• Summary stats (summarize_mathcanvas_results in mathcanvas.py): Align by_question_image_count and by_knowledge keys with the dataset so per-category and image-presence metrics count correctly (previously keys did not match).

Notes

No change to the judging logic; reporting / aggregation only, plus the hash update.

[clintonsteiner]

@dependabot rebase

[kennymckormick]

@shiwk24
There is one data sample changed in the new TSV file, please give a short introduction.

[shiwk24]

@shiwk24 There is one data sample changed in the new TSV file, please give a short introduction.

Sure, I have updated it.