Remove legacy logger

Migrate DefaultLogger implementation to SelectionSessionLogger.
This cleans up after the API refactor and fixes two bugs:
- All events are currently logged twice.
- Interfaces accept a null signature, but it currently crashes the legacy logger.

Bug: 73392698
Bug: 77659305
Test: atest FrameworksCoreTests:TextClassificationManagerTest
Test: atest FrameworksCoreTests:TextClassificationTest
Test: atest CtsViewTestCases:TextClassificationManagerTest
Test: atest CtsViewTestCases:TextClassifierValueObjectsTest
Test: atest CtsWidgetTestCases:TextViewTest
Test: atest CtsWidgetTestCases:EditTextTest
Test: Manually examined logs
Change-Id: I0d2b925abf5cab12d71fc2cc0fa527530c86ab10