- Add e1f2a3b4c5d6 migration: create dataset_review_sessions with FK ondelete='CASCADE' (matching the model). Previously created at runtime by init_db() → create_all(). - Update f0e9d8c7b6a5: change down_revision from a5b6c7d8e9f0 to e1f2a3b4c5d6 so the table exists when this migration runs. - All other create_all()-only tables (llm_providers, roles, validation_policies, llm_validation_results) already have guards (_table_exists()) in their respective migrations.
Generic single-database configuration.