Added optgroup elements to organize metrics into logical categories:
- Expected Standard
- Higher Standard
- Progress Scores
- Average Scores
- Gender Performance
- Equity (Disadvantaged)
- School Context
- 3-Year Trends
Also added CSS styling for optgroup labels to match the design system.
Note: School names in rankings are already clickable links to school details.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>