An index row for a directory inside a vault.
There is no parent_uuid. The filesystem already expresses the hierarchy, and
a second representation in the database is a second thing that can disagree
with the disk — so the tree is rebuilt from relative_path when the sidebar
needs it (PhoenixKitKnowledgeBase.Notes.folder_tree/1).
Folders play no part in [[wiki-link]] resolution, which matches on title
across the vault and only consults paths to break a tie.
Summary
Functions
Changeset for an indexed directory.