- Created dto.ts with all backend DTO types:
* RegisterRequest, RegisterResponse
* LoginRequest, LoginResponse
* UserResponse, TokenResponse
* RefreshRequest, ResendVerificationRequest
* ValidationError, ValidationErrors
- Updated api.ts to match backend DTOs:
* Added password_confirm to RegisterRequest
* Added remember_me to LoginRequest
* Added requires_2fa to AuthResult/LoginResponse
* Added value field to ValidationError details
- All types now match backend Go structs exactly
- Ensures type safety between frontend and backend