Refactor tests for PermissionManager, HostsManager, HostEntry, HostsFile, and HostsParser

- Updated test cases in test_manager.py to improve readability and consistency.
- Simplified assertions and mock setups in tests for PermissionManager.
- Enhanced test coverage for HostsManager, including edit mode and entry manipulation tests.
- Improved test structure in test_models.py for HostEntry and HostsFile, ensuring clarity in test cases.
- Refined test cases in test_parser.py for better organization and readability.
- Adjusted test_save_confirmation_modal.py to maintain consistency in mocking and assertions.

tests/test_save_confirmation_modal.py

@@ -279,7 +279,7 @@ class TestSaveConfirmationIntegration:
         """Test exit_edit_entry_mode cleans up properly."""
         app.entry_edit_mode = True
         app.original_entry_values = {"test": "data"}
-        
+
         # Mock the details_handler and query_one methods
         app.details_handler.update_entry_details = Mock()
         app.query_one = Mock()