Add support for selecting individual audio files during manual and bulk imports and pass that selection through the scan, API, job queue, processor and organizer.
Key changes:
- API: scan now returns audioFiles for each discovered book and emits a new 'grouping' progress phase; execute and manual-import routes accept file lists (audioFiles / selectedFiles) and validate them.
- Scanner: group loose audio files by metadata (title/author/narrator), deduplicate multi-part sets (CD1/CD2) across folders, and return audioFiles + groupingKey; add concurrency limit for ffprobe reads and merge groups post-scan.
- Job queue & processor: OrganizeFiles payload now includes selectedFiles; processors forward selectedFiles to the FileOrganizer and to cleanup logic.
- File organizer & cleanup: filter to only selectedFiles when organizing; cleanup now deletes only the selected files (if provided) instead of removing the whole directory.
- UI: Manual import browser and bulk import wizard updated to show per-file selection, track checkedFiles, toggle all, and send selected files to the API; ConfirmPhase updated to allow checking/unchecking files and prevents starting import with no files selected.
- Filesystem browse: removed expensive per-subfolder stats to keep browsing responsive (now lists subdirectories without nested stat calls).
Overall this change enables finer-grained imports, reduces accidental deletion of unselected files, and improves scan grouping for multi-folder audiobooks.
Introduce manual import workflow and download permission support. Adds a Prisma migration and schema field (users.download_access) to track per-user download access, and updates admin UI to toggle global and per-user download access. Implements new APIs: filesystem browse, manual-import endpoint, download-access settings, audiobook download-status, and on-demand download-token generation. Adds frontend components for manual import and related tests, plus documentation for the manual-import feature and the documentation-agent prompt. Key files: prisma/migrations/20260212000000_add_download_access_permission/migration.sql, prisma/schema.prisma, src/app/api/admin/filesystem/browse/route.ts, src/app/api/admin/manual-import/route.ts, src/app/api/admin/settings/download-access/route.ts, src/app/api/requests/[id]/download-token/route.ts, src/app/api/audiobooks/[asin]/download-status/route.ts, and updated admin users pages/components and permissions util.
kikootwo