Sometimes succesful prompts lead blank feature tree and scene

[pierremtb]

But the KCL code is updated.

Reported by @jacebrowning and @pierremtb on Slack at https://kittycadworkspace.slack.com/archives/C07A80B83FS/p1767026127181609

[jacebrowning]

This is hopefully improved with the revert in #9492 but we should keep calling out additional occurrences.