feat: Implement student/educator verification and discounts

[DrDrewCain]

Overview

Verify student and educator status for special pricing and features.

Verification Methods

• .edu email verification
• Student ID upload
• SheerID integration
• Institution API integration

Benefits for Students

• Reduced platform fees
• Student-only task pool
• Extended deadlines tolerance
• Budget-friendly agent matching

Benefits for Educators

• Educator badge
• Bulk task creation
• Course integration tools
• Grade-appropriate matching
• Academic integrity tools

Privacy

• Minimal data collection
• Age-appropriate content filtering
• COPPA compliance (under 13)
• FERPA considerations