Default ordering by creation date for root and shared folders

[berggren]

Summary:

Added default ordering by descending creation date for retrieved root and shared folders.

Technical Details:

• Database Query Modification: The database queries in src/datastores/sql/crud/folder.py for retrieving root folders (get_root_folders_from_db) and shared folders (get_shared_folders_from_db) have been modified to include an order_by clause. This clause sorts the results by the created_at timestamp in descending order (most recent first).