Officially support and document existing feature to protect LBs from auto deletion by service annotation

We got following response from support: "As far as creating a new annotation to disable deletion of the associated VPC LB resource, that support has already been done. There is an undocumented annotation that has already been created. This annotation was introduced in spring 2025 and it is available on all supported IKS and ROKS releases. It was not been included in the external documentation, because 
(1) no external user had ever requested this ability before. 
(2) We're not sure if this option should be exposed. Disabling the deleting of a VPC resource is not something that we generally want to promote. 
The syntax for this annotation is: service.kubernetes.io/ibm-load-balancer-cloud-provider-disable-features: "lb-delete"

We need this feature to protect our LBs from being deleted. We have 5 A/NLBs per cluster and they are added to DNS. If we just do a replace creation by accident, the hostname changes and we have an outage on prod of several hours. Please make disable-features: "lb-delete" an officially supported feature.