"Unable to create book from provided paths" when a book folder contains macOS `._` AppleDouble files

Books imported from a Mac-managed library fail with the generic "Unable to create book from provided paths" and no explanation. The folders contain AppleDouble sidecars like ._Track 01.mp3 alongside the real tracks. Server log:

WARN: [SCAN:api] Failed to create book for /path/to/books/<Author>/<Title>
Error: Command failed: ffprobe -i ".../._TA-CD-01.mp3" -show_format ...

Storyteller v2 in Docker, library on NFS.

Resolution: AppleDouble sidecars end in .mp3, so the file collector picked them up as audio tracks; ffprobe can't parse them, and the first failing file aborted the entire book import with the generic error. Storyteller now ignores OS metadata files (._* AppleDouble and .DS_Store) everywhere files are collected - the fix shipped in 2.14.17, so upgrade. On older versions, purge them from the library first, e.g. find /path/to/books -name '._*' -delete and find /path/to/books -name '.DS_Store' -delete; running dot_clean on the mount before importing also works. The same family of problem previously broke transcription via stray .DS_Store files.