Form Validation Schema-first validation using Zod as the single source of truth for both runtime validation and TypeScript types. Quick Start Core Principle: Reward Early, Punish Late This is the optimal validation timing pattern backed by UX research: | Event | Show Valid (✓) | Show Invalid (✗) | Why | |-------|----------------|------------------|-----| | On input | ✅ Immediately | ❌ Never | Don't yell while typing | | On blur | ✅ Immediately | ✅ Yes | User finished, show errors | | During correction | ✅ Immediately | ✅ Real-time | Let them fix quickly | Implementation Zod Schema Patterns Ba…