* Fixes#11335: Default manager for ObjectChange should filter by installed apps
* Employ canonical model discovery mechanism
* Move filtering logic to valid_models() queryset method
* fixed import to avoid content type does not exist
* Cleanup
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Co-authored-by: Abhimanyu Saharan <desk.abhimanyu@gmail.com>
* Initial work on #5913
* Provide per-line diff highlighting
* BulkDeteView should delete objects individually to secure a pre-change snapshot
* Add changelog tests for bulk operations
