- Rename error strings to use error_ prefix consistently
- Rename success strings to use success_ prefix
- Rename failure strings to use failed_ prefix
- Reorganize strings by feature groups with section comments
- Remove unused shortcuts.xml and manifest references
- Update all Kotlin code references
- Add AppSettingsScreen with update track selection and auto-check toggle
- Remove checkUpdateAvailable() as all vendors now support update checking
- Add missing Chinese translations for update-related strings