Design and bite-sized TDD plan for supporting Jellyfin libraries whose
collection type is 'mixed' (currently dropped silently by
JellyfinApiClient.Project), so music and standup content is ingested while
staying segregated from the main Movies / TV Shows libraries.
Key findings that shaped the design:
- Jellyfin classifies server-side via parentId + includeItemTypes, so the
three per-kind scanners see disjoint authoritative sets. No inference.
- No DB migration: MediaItem is TPT keyed on LibraryPathId, so
heterogeneous items under one library path are already legal.
- MediaKind is dispatch + presentation only; scheduling, playout,
collections and search carry zero references to it.
- Scoped to Jellyfin deliberately: local mixed libraries would have the
scanners claim each other's files and thrash LibraryFolder etags.
Blocked by #488 (JellyfinMusicVideoLibraryScanner crashes on first item).
Refs #489
timothy