W on a downloadable library node mirrors the subtree into /captures
(a fourth fsdy instance) like a bookmark, but downloads every track's
audio next to its toml; the toml points at the sibling by relative
name, so captures play with no provider round trip. Nodes opt in via
the new is_downloadable flags — Tidal blesses queueable and
track-listing nodes. The bookmark walk is now the shared capture walk
parameterized by a per-track sink.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>