- Added PermissionManager class for managing sudo permissions.
- Introduced HostsManager class for high-level operations on hosts file.
- Implemented methods for entering/exiting edit mode, toggling entries, moving entries, updating entries, saving the hosts file, and restoring backups.
- Integrated permission validation and backup creation during edit operations.
- Enhanced main application to support edit mode and associated actions.
- Added tests for PermissionManager and HostsManager to ensure functionality and error handling.