Multitenancy for the storage-target object store

[lisajulia]

• Check how this is done for the node version (https://github.com/cap-js/attachments)
• Doublecheck for usage without an object store!

[lisajulia]

Also see: #163 (comment)

Is is already sufficient to have prefixes for each file to simulate a folder structure?
-> Probably not.

[Schmarvinius]

Planned for Q1/2026