support resource detachment on RGI deletion

[a-hilaly]

Feature Description

Currently when deleting a ResourceGroup Instance (RGI), all managed sub resources are automatically deleted. We need to add support for a detach-on-deletion annotation (kro.run/detach-on-deletion: "true") that will release managed resources from kro's control without deleting them when the RGI is deleted. This will allow operators to preserve important resources for debugging, migration scenarios, or cases where resources need to outlive their parent RGI.

Example:

apiVersion: kro.run/v1alpha1
kind: Application
metadata:
  name: my-application
  annotations:
    kro.run/detach-on-deletion: "true"
spec:
  name: my-app
  image: nginx