- Paged loops now throw when they hit maxPages with a full last page, so a
truncated enumeration aborts the entity's collect and skips its prune
instead of deleting rows the sync never saw. The cap is injectable for
tests.
- Move sync serialization into SyncManager (tryLock coalesces duplicate
requests) and construct SyncService there; SourceRepository only exposes
the active MusicSource. Removes the repo <-> sync import cycle.
- Re-throw CancellationException instead of reporting a cancelled sync as
failed.
- Add buffer(1) to the outer albums/songs/playlistSongs flows so their
flowOn channel cannot hold 64 batches.
- Rank prefetch is best-effort (missing frequent/recent no longer aborts
the album sync).
- Skip playlist entries without an id, keeping positions contiguous.
- Chunk stale-disc deletes like the other prunes.
- Update the implementation plan line that still described the old
single-transaction sync.
adds docs/architecture.md (stack, layers, data model, sync, search, networking, testing, CI), docs/implementation-plan.md (phases and status), and AGENTS.md for agents and contributors