fix: Schedule Update on Segment Overrides shows 'Feature contains no changes'

[talissoncosta]

Description

When clicking Schedule Update on the Segment Overrides tab of the Edit Feature modal, users see a "Feature contains no changes" error instead of the scheduling modal opening.

Root Cause

In frontend/web/components/modals/create-feature/index.js, saveFeatureSegments delegates to saveFeatureValue() without forwarding the schedule argument (line 803):

const saveFeatureSegments = saveFeatureWithValidation(
  (schedule) => {
    this.setState({ segmentsChanged: false })
    if ((is4Eyes || schedule) && isVersioned && !identity) {
      return saveFeatureValue()  // ← missing `schedule` argument
    } else {
      this.save(editFeatureSegments, isSaving)
    }
  },
)

When is4Eyes is false, the lost schedule flag causes the code to skip the change request flow entirely and attempt a direct value save — which fails because there are no value tab changes.

Suggested follow-up

Add E2E test coverage for scheduling segment override updates — there is currently none. The test should:

1. Create an environment, feature, and segment
2. Open the feature, go to the Segment Overrides tab
3. Add/modify a segment override
4. Click "Schedule Update"
5. Assert the scheduling modal opens (not "Feature contains no changes")