api: replace manual XValidation CEL rule with ExactlyOneOf marker on ClusterObjectSetObject (#2620)

Use the +kubebuilder:validation:ExactlyOneOf={object,ref} marker
introduced in controller-tools v0.19.0 instead of a hand-written
CEL XValidation rule. The generated CEL expression is semantically
equivalent.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: pedjak

api/v1/clusterobjectset_types.go

@@ -395,7 +395,7 @@ type ClusterObjectSetPhase struct {
 //
 // Exactly one of object or ref must be set.
 //
-// +kubebuilder:validation:XValidation:rule="has(self.object) != has(self.ref)",message="exactly one of object or ref must be set"
+// +kubebuilder:validation:ExactlyOneOf={object,ref}
 type ClusterObjectSetObject struct {
 	// object is an optional embedded Kubernetes object to be applied.
 	//

helm/olmv1/base/operator-controller/crd/experimental/olm.operatorframework.io_clusterobjectsets.yaml

@@ -232,8 +232,10 @@ spec:
                             type: object
                         type: object
                         x-kubernetes-validations:
-                        - message: exactly one of object or ref must be set
-                          rule: has(self.object) != has(self.ref)
+                        - message: exactly one of the fields in [object ref] must
+                            be set
+                          rule: '[has(self.object),has(self.ref)].filter(x,x==true).size()
+                            == 1'
                       maxItems: 50
                       type: array
                   required:

manifests/experimental-e2e.yaml

@@ -1556,8 +1556,10 @@ spec:
                             type: object
                         type: object
                         x-kubernetes-validations:
-                        - message: exactly one of object or ref must be set
-                          rule: has(self.object) != has(self.ref)
+                        - message: exactly one of the fields in [object ref] must
+                            be set
+                          rule: '[has(self.object),has(self.ref)].filter(x,x==true).size()
+                            == 1'
                       maxItems: 50
                       type: array
                   required:

manifests/experimental.yaml

@@ -1517,8 +1517,10 @@ spec:
                             type: object
                         type: object
                         x-kubernetes-validations:
-                        - message: exactly one of object or ref must be set
-                          rule: has(self.object) != has(self.ref)
+                        - message: exactly one of the fields in [object ref] must
+                            be set
+                          rule: '[has(self.object),has(self.ref)].filter(x,x==true).size()
+                            == 1'
                       maxItems: 50
                       type: array
                   required: