Davy7/20/2026, 8:07:14 PM

load_playback_source returned Ok(None) for remote stems in the streaming
path, but the fallback load_playback_source never called
ensure_remote_stem_files_cached before decoding. A cold-cache remote-stems
song reached load_remote_stems_playback_source with no files on disk and
failed to decode. Now load_playback_source downloads missing stems first.

Also clean up verified temp files when a later stem in the set fails
download, zero-byte validation, or decode validation, so rejected sets do
not leave partial temp files on disk.

Parent99f9da8