[Feature Sugestion] Allow indexing of assets in subfolders

[Typhonragewind]

Pretty much what it says in the title. It would be useful to be able to use subfolders on the main data folder:

• Easier to import existing images
• Keeps some low tech organization in case of app technical issues
• In docker, allows for easy mounting of other folders without having to move pictures around

[neonwatty]

Solved in the new "pro" version of the app!