Support eBook normalization

[masonfox]

Similar to LazyLibrarian, but more streamlined, support Claude normalization and library addition for ebooks: epub, mobi, and azw3 files and allow the user to configure their preferred file format.

Workflow:

1. Read file metadata with ffprobe
2. Use the Hardcover API as a primary metadata provider after an initial Claude normalization
3. Apply Hardcover API response data, overwriting existing metadata
4. Allow custom AI instructions for in .env for final Claude polish and resend to Claude. For example, I'd like for all book descriptions to not have review content in them - remove those.
5. Using Calibre CLI, add the book to your Calibre Library with normalized metadata