This update adds S3 management APIs for viewing storage usage, listing cached answer sheets and score sheets, and deleting stored files.

Exam results now have an all-scores API with pagination, filtering, search, and sorting. Score sheet export uses the VIEW_EXAM_DATA permission, with SCHOOL users limited to their own school.

Administrators can now publish exams locally for individual schools before ZhiXue officially releases them. Students can access their own results when their scores are already stored. Score retrieval also handles missing totals and rankings while marking is still in progress.

Answer sheets now show subquestion scores, step scores, and teacher scoring records more clearly, with improved indentation and positioning.

The backend now requires Python 3.11 and uses psycopg 3. Dependencies were upgraded, and a database migration was added for per-school exam publication status.