Editor script can't find a class outside of Editor folder

Hello all,

So first off, I'm using the GTF preview package to create a dialogue sequence editor. I've done this in the old Graph View API, but the GTF offers so much more in the quality of life areas.

Here's my issue, I need to make class and scriptable object references (that are out side the this Editor folder) on some nodes. But no matter my namespace configurations or using <namespace>; set up I cannot get it to find my classes. always retuning that dreaded error CS0246: The type or namespace name 'MyScriptableObj' could not be found (are you missing a using directive or an assembly reference?).

Now because of how early in development GTF is, It seems I need to have an assembly definition (.asmdef file) referencing the GTF namespaces in the editor folder to code with the api at all. I've tried to work around this but assembly definitions are pretty new to me, I don't actually know what it's doing to make the GTF namespaces available. I've discovered that If I move the assembly def to the root assets folder (would never do in practice) my nodes have access to the scriptable objects I need. but I can no longer build the game.

I'm hoping someone could explain assembly definitions to me and if it's actually the reason for making my scrapable objects inaccessible, and if so how I can let it allow access to my classes.

Regardless I thinking it's far to early to use GTF to the extent I'd need it, looking at the way it saves graphs it looks like I wouldn't be able to really use it in builds of the app.

Thanks in advance, Sorry if this is a stupid question. Been doing this for 5 years but I always seem to have these sort of questions lol