[Storage] Split Object Storage to its own Component

[velvia]

Part of the initiative to move towards more modular storage, and also important for scalability and maintainability.

The object storage covers existing objects, parent_sync, owners tables at the very least, and it covers things such as GC of older objects, knowing which objects are active.
It should also be responsible for object indexing.

[github-actions]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days.

[velvia]

We need to keep this one open.