KEP-4358: Custom Resource Field Selectors: Promote to Beta (#46980)

* KEP-4358: Custom Resource Field Selectors: Promote to Beta

* Update content/en/docs/reference/command-line-tools-reference/feature-gates/custom-resource-field-selectors.md

Co-authored-by: Dipesh Rawat <rawat.dipesh@gmail.com>

* Remove alpha level notes about enabling the feature

* Update content/en/docs/tasks/extend-kubernetes/custom-resources/custom-resource-definitions.md

Co-authored-by: Tim Bannister <tim@scalefactory.com>

* Update content/en/docs/tasks/extend-kubernetes/custom-resources/custom-resource-definitions.md

Co-authored-by: lakshmi prasuna <56723673+T-Lakshmi@users.noreply.github.com>

* Update content/en/docs/concepts/extend-kubernetes/api-extension/custom-resources.md

Co-authored-by: lakshmi prasuna <56723673+T-Lakshmi@users.noreply.github.com>

---------

Co-authored-by: Dipesh Rawat <rawat.dipesh@gmail.com>
Co-authored-by: Tim Bannister <tim@scalefactory.com>
Co-authored-by: lakshmi prasuna <56723673+T-Lakshmi@users.noreply.github.com>

content/en/docs/concepts/extend-kubernetes/api-extension/custom-resources.md

@@ -313,13 +313,10 @@ may also be used with field selectors when included in the `spec.versions[*].sel
 
 {{< feature-state feature_gate_name="CustomResourceFieldSelectors" >}}
 
-You need to enable the `CustomResourceFieldSelectors`
-[feature gate](/docs/reference/command-line-tools-reference/feature-gates/) to
-use this behavior, which then applies to all CustomResourceDefinitions in your
-cluster.
-
 The `spec.versions[*].selectableFields` field of a {{< glossary_tooltip term_id="CustomResourceDefinition" text="CustomResourceDefinition" >}} may be used to
-declare which other fields in a custom resource may be used in field selectors.
+declare which other fields in a custom resource may be used in field selectors
+with the feature of `CustomResourceFieldSelectors`
+[feature gate](/docs/reference/command-line-tools-reference/feature-gates/) (This feature gate is enabled by default since Kubernetes v1.31).
 The following example adds the `.spec.color` and `.spec.size` fields as
 selectable fields.
 

content/en/docs/reference/command-line-tools-reference/feature-gates/custom-resource-field-selectors.md

@@ -9,6 +9,10 @@ stages:
   - stage: alpha
     defaultValue: false
     fromVersion: "1.30"  
+    toVersion: "1.30"
+  - stage: beta
+    defaultValue: true
+    fromVersion: "1.31"  
 ---
 
 Enable `selectableFields` in the

content/en/docs/tasks/extend-kubernetes/custom-resources/custom-resource-definitions.md

@@ -1686,13 +1686,14 @@ may also be used with field selectors when included in the `spec.versions[*].sel
 
 {{< feature-state feature_gate_name="CustomResourceFieldSelectors" >}}
 
-You need to enable the `CustomResourceFieldSelectors`
-[feature gate](/docs/reference/command-line-tools-reference/feature-gates/) to
-use this behavior, which then applies to all CustomResourceDefinitions in your
-cluster.
-
+For Kubernetes {{< skew currentVersion >}} the ability to define field selectors for
+custom resources is available by default (enabled by default since Kubernetes v1.31);
+you can disable it for your cluster  by turning off the `CustomResourceFieldSelectors`
+[feature gate](/docs/reference/command-line-tools-reference/feature-gates/).
 The `spec.versions[*].selectableFields` field of a {{< glossary_tooltip term_id="CustomResourceDefinition" text="CustomResourceDefinition" >}} may be used to
-declare which other fields in a custom resource may be used in field selectors.
+declare which other fields in a custom resource may be used in field selectors
+with the feature of `CustomResourceFieldSelectors`
+[feature gate](/docs/reference/command-line-tools-reference/feature-gates/) (This feature gate is enabled by default since Kubernetes v1.31).
 The following example adds the `.spec.color` and `.spec.size` fields as
 selectable fields.