Allow "copy-from" to keep variant data.

[nemesis688]

Is your feature request related to a problem? Please describe.

"copy-from" Doesn't seem to preserve "variants" data. When using "copy-from" to make tweaks for a mod the various variants get wiped out if you don't include the entire list. Which, in effect, replaces the list. Making targeted changes a bit harder and less obvious as whats an intentional change and what isn't.

For example, I wanted to edit the "pocket_data" of the smartphone case to allow Aftershocks 'Atomic Smartphone' to fit. Having to include the entire list makes the tweak less targeted and can cause issues if the list of variants gets expanded or reduced.

I can see the utility when you are using "copy-from" for a new item to not automatically bring in the variants data with it but that could be accomplished by having a variant list of one like how several firearms are currently set up.

Additionally the "extend" field does not work with variants data so if someone wants to add a new variant of an item they have to include and overwrite the whole list to do so.

Solution you would like.

I would appreciate it if the code governing "copy-from" could be tweaked to allow the variants data to be preserved. It would also be nice if "extend" could interact with variant data.

Describe alternatives you have considered.

Simply not making the request and keep including more data than needed in targeted tweaks.

Additional context

No response