fix(blueprints): correct auth import and decorator call in tasks_bp

- Changed 'from auth import require_auth' → 'from middleware import require_auth'
- Added missing parentheses: @require_auth → @require_auth()
- Prevents 'No module named auth' and endpoint name collision errors

pos/blueprints/tasks_bp.py

@@ -1,14 +1,14 @@
 """Blueprint for background task management (Celery)."""
 
 from flask import Blueprint, jsonify, request
-from auth import require_auth
+from middleware import require_auth
 from tasks import warm_vehicle_cache_task, generate_report_task
 
 tasks_bp = Blueprint('tasks', __name__, url_prefix='/pos/api/tasks')
 
 
 @tasks_bp.route('/warm-cache', methods=['POST'])
-@require_auth
+@require_auth()
 def enqueue_warm_cache():
     """Enqueue vehicle cache warming task."""
     task = warm_vehicle_cache_task.apply_async()
@@ -16,7 +16,7 @@ def enqueue_warm_cache():
 
 
 @tasks_bp.route('/report', methods=['POST'])
-@require_auth
+@require_auth()
 def enqueue_report():
     """Enqueue report generation task."""
     data = request.get_json() or {}