refactor: centralize initialization logic in dedicated service

- Create initialization_service.py with shared initialization functions
- Extract setup logic from lifespan and setup endpoint into reusable functions
- Setup endpoint now calls perform_initial_setup() directly
- Lifespan startup calls the same shared functions
- Eliminates code duplication between setup and lifespan
- Ensures consistent initialization behavior regardless of entry point

src/server/api/auth.py

@@ -117,46 +117,26 @@ async def setup_auth(req: SetupRequest):
         # Save the config with all updates
         config_service.save_config(config, create_backup=False)
         
-        # Sync series from data files to database if anime directory is set
-        if anime_directory:
-            try:
-                import structlog
-
-                from src.server.database.connection import get_db_session
-                from src.server.database.system_settings_service import (
-                    SystemSettingsService,
-                )
-                from src.server.services.anime_service import (
-                    sync_series_from_data_files,
-                )
-                logger = structlog.get_logger(__name__)
-                sync_count = await sync_series_from_data_files(
-                    anime_directory, logger
-                )
-                logger.info(
-                    "Setup complete: synced series from data files",
-                    count=sync_count
-                )
-                
-                # Mark initial scan as completed
-                try:
-                    async with get_db_session() as db:
-                        await SystemSettingsService.mark_initial_scan_completed(
-                            db
-                        )
-                    logger.info("Marked initial scan as completed")
-                except Exception as mark_error:
-                    logger.warning(
-                        "Failed to mark initial scan as completed",
-                        error=str(mark_error)
-                    )
-            except Exception as e:
-                # Log but don't fail setup if sync fails
-                import structlog
-                structlog.get_logger(__name__).warning(
-                    "Failed to sync series after setup",
-                    error=str(e)
-                )
+        # Perform initial setup (series sync, NFO scan, media scan)
+        # This ensures everything is initialized immediately after setup
+        # without requiring an application restart
+        # Reload settings to pick up the new configuration
+        from src.config.settings import settings
+        from src.server.services.initialization_service import (
+            perform_initial_setup,
+            perform_nfo_scan_if_needed,
+        )
+        settings.reload()
+        
+        # Perform the initial series sync and mark as completed
+        await perform_initial_setup()
+        
+        # Perform NFO scan if configured
+        await perform_nfo_scan_if_needed()
+        
+        # Note: Media scan is skipped during setup as it requires
+        # background_loader service which is only available during
+        # application lifespan. It will run on first application startup.
         
         return {"status": "ok"}