Provider-neutral playlist import/export

JamRelay exposes preview_playlist_import, import_playlist and export_playlist. These operations work without a connected provider and do not perform provider writes. A separate, explicit transfer/write operation is required to publish imported tracks.

Input formats

• JSON — native jamrelay-playlist document, currently version: 1, with an ordered tracks array. Each track may include canonical track_id and optional provider mapping provenance.
• CSV — the header is position,title,artist,album,uri,track_id,provider_id,connection_id,provider_track_id,provider_uri. Fields use standard CSV quoting; Unicode is supported.
• M3U8 — UTF-8 #EXTM3U playlists. #EXTINF:seconds,Artist - Title metadata is optional; each following non-comment line is an ordered URI.
• TXT — UTF-8 tab-separated columns title, artist, album, uri. The header is optional.

Order and duplicate entries are preserved. Items without a canonical ID, provider mapping or URI are returned in unresolved; the parser never invents an identity. Input is bounded to 1 MiB and 10,000 tracks, with at most 50 structured parse/validation errors reported.