Problem: Child descriptions created "on the fly" do not appear in treeview after clicking Save

### Current Behavior

**Steps to reproduce the behaviour**

1. Under the Add menu, click on Archival Description.
2. Within the description edit template go to "Add new child levels."
3. Add a new child record (any level) and click Save.
4. The child description created "on the fly" from the parent description will not be visible in treeview.
5. The child description will **only** appear in the treeview if you click "Edit" and "Save" once more.

### Expected Behavior

Child descriptions created "on the fly" should appear instantly under the parent description in treeview when you click "Save" the first time.

### Possible Solution

_No response_

### Context and Notes

This issue only appears when you add new child levels for the **first time**. If you've already added child levels "on the fly" to a given description, and then add more later, they appear instantly in the treeview as expected.

### Version used

AtoM 2.8.2

### Operating System and version

_No response_

### Default installation culture

_No response_

### PHP version

_No response_

### Contact details

_No response_

Reproduce the issue through the archival description edit template's “Add new child levels” workflow, then trace what happens to the treeview after the first Save. Done means a newly created child appears immediately under its parent on the first save, with the existing behavior for later additions preserved.

Written by the indexing model from the issue text.