- support GitHub, GitCode, gh-proxy, and ghfast sources
- automatically try other sources when version checks fail
- persist the working fallback source and sync the UI immediately
- update translations, configuration migration, and source tests
- Add a GitCode source toggle to Version Management
- Persist the preferred download source
- Prefer GitCode for app and core updates with GitHub fallback
- Add localized copy, documentation, and download-order tests
- split Tauri business logic out of main.rs by domain
- separate agent and core configuration submodules
- organize Rust tests by feature with shared test support
- split frontend locale resources