fix: Remove duplicate update_customer_plan function

backend/app/routes/admin.py

@@ -497,48 +497,6 @@ def get_customer(customer_id):
         }), 500
 
 
-@admin_bp.route('/customers/<int:customer_id>/plan', methods=['PUT'])
-def update_customer_plan(customer_id):
-    """Müşterinin planını güncelle"""
-    try:
-        data = request.json
-        customer = Customer.query.get(customer_id)
-
-        if not customer:
-            return jsonify({
-                "status": "error",
-                "message": "Müşteri bulunamadı"
-            }), 404
-
-        # Update plan
-        if 'subscription_plan' in data:
-            customer.subscription_plan = data['subscription_plan']
-
-        if 'max_domains' in data:
-            customer.max_domains = data['max_domains']
-
-        if 'max_containers' in data:
-            customer.max_containers = data['max_containers']
-
-        if 'subscription_status' in data:
-            customer.subscription_status = data['subscription_status']
-
-        db.session.commit()
-
-        return jsonify({
-            "status": "success",
-            "message": "Plan başarıyla güncellendi",
-            "customer": customer.to_dict()
-        })
-
-    except Exception as e:
-        db.session.rollback()
-        return jsonify({
-            "status": "error",
-            "message": f"Plan güncellenirken hata: {str(e)}"
-        }), 500
-
-
 @admin_bp.route('/customers/<int:customer_id>', methods=['PUT'])
 def update_customer(customer_id):
     """Müşteri bilgilerini güncelle"""