- Add avatar upload with file picker dialog
- Display avatars in header, chat messages, and settings
- Implement clickable avatars with full-screen zoom modal
- Enable asset protocol for local file access in Tauri config
- Add tauri-plugin-dialog for native file selection
- Store avatars in ~/.config/claudia/avatars/
- Support PNG, JPG, JPEG, and WEBP formats
- Modal closes on overlay click or ESC key
