* Add style prop to UserAvatar component for better customization
* Refactor UserAvatar to use getAvatarSeed utility for consistent avatar generation
* Fix React hook ordering issues in profile/overview.tsx to prevent crashes during auth state changes
* Add proper state initialization and cleanup during authentication transitions
* Ensure consistent fallback avatar display for unauthenticated users
These changes improve stability during login/logout operations and provide better visual continuity with Robohash avatars when profile images aren't available.
