"origin" keyvalue cannot be set on func_dustcloud/dustmote

[AlexanderFurby]

Describe the bug

Leaving smart edit and adding a new keyvalue called "origin" to a func_dustcloud/dustmote deletes the keyvalue when applied (applying it in and out of smart edit mode has the same effect).

To Reproduce

Create a func_dustcloud or func_dustmote entity. Exit Smart Edit mode and add a new keyvalue called "origin" and assign it the value of 0 0 0. Click apply, and observe that it has not applied.

Issue Map

All.

Expected Behavior

It should apply it as a new keyvalue, not delete it.

Operating System

Windows 11