Also change the checkbox dropdown to a more interactive tomselect (type-to-search dropdown with chips) with pictures.
This makes it so data sources can be added to a timeline dynamically.
In the future, data sources can be implemented externally and push data to the timeline, so these need to not be rigidly hard-coded into the app and assumed to never change.
This essentially adds all their info (name, title, description, image, etc) into each timeline DB.
