This pull request refactors the TUI (terminal user interface) to replace the old "Databases" screen with a new "Backups" screen, updates navigation and UI hints, and improves configuration struct accessibility. The changes also clean up unused code and make the configuration available throughout the app.

Screen and Navigation Refactor:

• Replaced the "Databases" screen with a new BackupsScreen, updating all references and navigation logic to use "Backups" instead of "Databases" (src/ui/app.rs, src/ui/screens/home.rs, src/ui/screens/mod.rs, src/ui/screens/backups.rs, src/ui/screens/databases.rs) [1] [2] [3] [4] [5] [6] [7].
• Added navigation: pressing Backspace on "Backups" or "Settings" returns to the main screen, and updated key handling for list navigation in both "Main" and "Backups" screens (src/ui/app.rs).

UI and Layout Improvements:

• Updated the main layout to show context-sensitive hints (e.g., "Backspace to go back" on sub-screens) and passed the App struct to all screen draw functions for more flexible rendering (src/ui/screens/layout.rs, src/ui/screens/home.rs, src/ui/screens/settings.rs) [1] [2] [3] [4].

Configuration Struct Accessibility:

• Made all fields in the Config and related backup structs (Backup, BackupDatastore, BackupSchedule) public, allowing screens to access backup configuration data for display and logic (src/utils/config.rs) [1] [2].

App Initialization:

• Updated the main entry point and App initialization to accept and store the Config object, making configuration available to all UI components (src/main.rs, src/ui/app.rs) [1] [2].

Code Cleanup:

• Removed the now-unused DatabasesScreen and its module (src/ui/screens/databases.rs, src/ui/screens/mod.rs) [1] [2].