Disable editing default value streams

While we work to fix issues with editing default streams
https://gitlab.com/gitlab-org/gitlab/-/issues/321959 we
need to disable editing of default streams

ee/app/assets/javascripts/analytics/cycle_analytics/components/create_value_stream_form/constants.js

@@ -37,6 +37,9 @@ export const i18n = {
   ISSUE_STAGE_END: s__('CreateValueStreamForm|Issue stage end'),
   PLAN_STAGE_START: s__('CreateValueStreamForm|Plan stage start'),
   CODE_STAGE_START: s__('CreateValueStreamForm|Code stage start'),
+  DEFAULT_STAGE_FEATURES: s__(
+    'CreateValueStreamForm|Default stages can only be hidden or re-ordered',
+  ),
 };
 
 export const ERRORS = {

ee/app/assets/javascripts/analytics/cycle_analytics/components/create_value_stream_form/default_stage_fields.vue

@@ -66,14 +66,15 @@ export default {
         :state="isValid('name')"
         :invalid-feedback="renderError('name')"
         :data-testid="`default-stage-name-${index}`"
+        :description="$options.i18n.DEFAULT_STAGE_FEATURES"
       >
         <!-- eslint-disable vue/no-mutating-props -->
         <gl-form-input
           v-model.trim="stage.name"
           :name="`create-value-stream-stage-${index}`"
           :placeholder="$options.i18n.FORM_FIELD_STAGE_NAME_PLACEHOLDER"
+          disabled="disabled"
           required
-          @input="$emit('input', $event)"
         />
         <!-- eslint-enable vue/no-mutating-props -->
       </gl-form-group>
@@ -84,7 +85,10 @@ export default {
         @hide="$emit('hide', $event)"
       />
     </div>
-    <div class="gl-display-flex gl-align-items-center" :data-testid="`stage-start-event-${index}`">
+    <div
+      class="gl-display-flex gl-align-items-center gl-mt-2"
+      :data-testid="`stage-start-event-${index}`"
+    >
       <span class="gl-m-0 gl-vertical-align-middle gl-mr-2 gl-font-weight-bold">{{
         $options.i18n.DEFAULT_FIELD_START_EVENT_LABEL
       }}</span>

ee/spec/frontend/analytics/cycle_analytics/components/create_value_stream_form/default_stage_fields_spec.js

@@ -56,6 +56,10 @@ describe('DefaultStageFields', () => {
     expect(findStageFieldName().html()).toContain(defaultStage.name);
   });
 
+  it('disables input for the stage field name', () => {
+    expect(findStageFieldName().attributes('disabled')).toBe('disabled');
+  });
+
   it('renders the field start event', () => {
     expect(findStartEvent().exists()).toBe(true);
     expect(findStartEvent().html()).toContain(ISSUE_CREATED.name);
@@ -72,12 +76,12 @@ describe('DefaultStageFields', () => {
     expect(content).toContain(defaultStage.endEventLabel);
   });
 
-  it('on field input emits an input event', () => {
+  it('does not emits any input', () => {
     expect(wrapper.emitted('input')).toBeUndefined();
 
     const newInput = 'coooool';
     findStageFieldName().vm.$emit('input', newInput);
-    expect(wrapper.emitted('input')[0]).toEqual([newInput]);
+    expect(wrapper.emitted('input')).toBeUndefined();
   });
 
   describe('StageFieldActions', () => {

locale/gitlab.pot

@@ -8666,6 +8666,9 @@ msgstr ""
 msgid "CreateValueStreamForm|Default stages"
 msgstr ""
 
+msgid "CreateValueStreamForm|Default stages can only be hidden or re-ordered"
+msgstr ""
+
 msgid "CreateValueStreamForm|Edit Value Stream"
 msgstr ""