Add DLC relations to items/search

I'd noticed this with genes/Rimworlds Biotech DLC, it could be another useful way of filtering 

https://steamcommunity.com/sharedfiles/filedetails/?id=2878104853

<img width="1105" height="1129" alt="Image" src="https://github.com/user-attachments/assets/f549f92d-5ad7-49ef-af0b-f36d96ea5179" />