Update ContractsPage to match TokenPage formatting style

- Import TokenPage.css for consistent clean styling
- Restructure contracts layout to use section-based approach
- Replace complex grid with clean model-card design
- Update button styles to match cta-btn patterns
- Add filter buttons with TokenPage color scheme
- Improve typography and spacing consistency
- Use stats-grid layout for overview section

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: b0ase