fix: allow quiz answer textarea vertical resize

[mtsui-cmyk]

Description

Allow vertical resizing for the quiz answer textarea in QuizViewer so users can expand the input area for longer written or coding answers.

Related Issues

• Closes [Feature Request]: Allow user-resizing of answer textarea in Quiz component, ie. add 'resize:vertical' CSS property #475

Module(s) Affected

• web (Frontend)

Checklist

• I have read and followed the contribution guidelines.
• My code follows the project's coding standards.
• I have run pre-commit run --all-files and fixed any issues.
• I have added relevant tests for my changes.
• I have updated the documentation (if necessary).
• My changes do not introduce any new security vulnerabilities.

Additional Notes

Validated the changed file with:

• uvx pre-commit run --files web/components/quiz/QuizViewer.tsx
• npx eslint components/quiz/QuizViewer.tsx

This change is intentionally minimal: it only replaces resize-none with resize-y for the answer textarea in the quiz viewer.