Deletion (d) previously reached only top-level folders of editable
stores. /captures now exposes its whole tree: nested folders delete
recursively, single tracks delete their metadata file plus the
downloaded audio next to it (never audio outside the instance root).
Tracks advertise this through the new LibraryNode.tracks_deletable
flag. Because these deletes destroy slow-to-redo downloads, the TUI
asks delete <title>? [y/N] first; cheap deletables (search terms,
bookmarks, saved queues) stay unconfirmed.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>