get_recent_images and search_images_by_prompt take limit/offset so the recent
and search image routes no longer over-fetch a 5000-row window and slice it.
generate_content_hash, PromptModel.migrate_database and find_duplicates had no
callers outside their own tests. The isolated logger tests re-apply their
thread filter after update_config rebuilds the handlers. Long lines in the
touched database and image modules are wrapped so the full flake8 hook passes.
Vito Sansevero
0393d01746