feat: enhance Letzshop jobs and order management

- Add job cancellation and retry functionality
- Improve jobs table with better status display
- Add background task improvements
- Update Letzshop order service
- Update documentation

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/tasks/background_tasks.py

@@ -5,6 +5,7 @@ import logging
 from datetime import UTC, datetime
 
 from app.core.database import SessionLocal
+from app.services.admin_notification_service import admin_notification_service
 from app.utils.csv_processor import CSVProcessor
 from models.database.marketplace_import_job import MarketplaceImportJob
 from models.database.vendor import Vendor
@@ -88,6 +89,16 @@ async def process_marketplace_import(
             job.status = "completed_with_errors"
             job.error_message = f"{result['errors']} rows had errors"
 
+            # Notify admin if error count is significant
+            if result.get("errors", 0) >= 5:
+                admin_notification_service.notify_import_failure(
+                    db=db,
+                    vendor_name=vendor.name,
+                    job_id=job_id,
+                    error_message=f"Import completed with {result['errors']} errors out of {result['total_processed']} rows",
+                    vendor_id=vendor_id,
+                )
+
         db.commit()
         logger.info(
             f"Import job {job_id} completed: "
@@ -102,6 +113,17 @@ async def process_marketplace_import(
                 job.status = "failed"
                 job.error_message = str(e)
                 job.completed_at = datetime.now(UTC)
+
+                # Create admin notification for import failure
+                vendor_name = vendor.name if vendor else f"Vendor {vendor_id}"
+                admin_notification_service.notify_import_failure(
+                    db=db,
+                    vendor_name=vendor_name,
+                    job_id=job_id,
+                    error_message=str(e)[:200],  # Truncate long errors
+                    vendor_id=vendor_id,
+                )
+
                 db.commit()
             except Exception as commit_error:
                 logger.error(f"Failed to update job status: {commit_error}")