- Added command classes: ToggleEntryCommand, MoveEntryCommand, AddEntryCommand, DeleteEntryCommand, UpdateEntryCommand.
- Integrated UndoRedoHistory to manage command execution and history.
- Updated HostsManager to use command-based methods for editing entries with undo/redo support.
- Enhanced HostsManagerApp to display undo/redo status and handle undo/redo actions via keyboard shortcuts.
- Refactored navigation handler to utilize command-based methods for toggling and moving entries.
- Created comprehensive tests for command classes and integration with HostsManager.
