Fix 500 error when saving review settings in Docker by ensuring required database tables are created during SettingsService initialization.
- Add review_sources table creation with proper schema (id, source_name, enabled, display_order, max_variants, priority, conditions, timestamps)
- Add review_settings table creation with proper schema (id, setting_key, setting_value, description, timestamps)
- Initialize default review sources (IMDb, TMDb, Metacritic, etc.) if table is empty
- Ensures Docker containers have all required tables for review functionality
Resolves issue where frontend review settings save would fail with "no such table: review_sources" error in Docker environment.