Add background print dispatching + tests

backend/app/main.py

@@ -237,70 +237,6 @@ if not app_settings.debug:
 
 logging.info("Bambuddy starting - debug=%s, log_level=%s", app_settings.debug, log_level_str)
 
-from backend.app.api.routes import (
-    ams_history,
-    api_keys,
-    archives,
-    auth,
-    camera,
-    cloud,
-    discovery,
-    external_links,
-    filaments,
-    firmware,
-    github_backup,
-    groups,
-    inventory,
-    kprofiles,
-    library,
-    local_presets,
-    maintenance,
-    metrics,
-    notification_templates,
-    notifications,
-    pending_uploads,
-    print_log,
-    print_queue,
-    printers,
-    projects,
-    settings as settings_routes,
-    smart_plugs,
-    spoolman,
-    support,
-    system,
-    updates,
-    users,
-    virtual_printers,
-    webhook,
-    websocket,
-)
-from backend.app.api.routes.maintenance import _get_printer_maintenance_internal, ensure_default_types
-from backend.app.api.routes.support import init_debug_logging
-from backend.app.core.database import async_session, init_db
-from backend.app.core.websocket import ws_manager
-from backend.app.models.smart_plug import SmartPlug
-from backend.app.services.archive import ArchiveService
-from backend.app.services.bambu_ftp import download_file_async, get_ftp_retry_settings, with_ftp_retry
-from backend.app.services.bambu_mqtt import PrinterState
-from backend.app.services.github_backup import github_backup_service
-from backend.app.services.homeassistant import homeassistant_service
-from backend.app.services.mqtt_relay import mqtt_relay
-from backend.app.services.mqtt_smart_plug import mqtt_smart_plug_service
-from backend.app.services.notification_service import notification_service
-from backend.app.services.print_scheduler import scheduler as print_scheduler
-from backend.app.services.printer_manager import (
-    init_printer_connections,
-    printer_manager,
-    printer_state_to_dict,
-)
-from backend.app.services.smart_plug_manager import smart_plug_manager
-from backend.app.services.spoolman import close_spoolman_client, get_spoolman_client, init_spoolman_client
-from backend.app.services.spoolman_tracking import (
-    cleanup_tracking as _cleanup_spoolman_tracking,
-    report_usage as _report_spoolman_usage,
-    store_print_data as _store_spoolman_print_data,
-)
-from backend.app.services.tasmota import tasmota_service
 
 # Track active prints: {(printer_id, filename): archive_id}
 _active_prints: dict[tuple[int, str], int] = {}