Add a new `--keep-filenames` boolean flag (no shorthand, default false) on
both `optimize` and `watch` commands. When enabled, page entries in the
output CBZ preserve their original base filenames instead of being
renumbered to `%04d` sequential indices. Extension is swapped on format
conversion (e.g. `001.png` → `001.webp`), split pages get `-NN` suffixes
on the original stem, and duplicate base names fall back to
`<stem>_<index>.<ext>`. Watch mode supports the flag via the
`keep-filenames` viper config key.
Design: data-driven `OriginalName` field on `manga.PageFile`, set at
extraction in `cbz_loader.ExtractChapter`. The `Converter` interface is
unchanged. Flag off → behavior identical to before.
Closes#216
- Remove NoOptDefVal which caused the format flag to fail with space-separated values
- Add 5 comprehensive unit tests for format flag: space syntax, short form, equals syntax, default value, and case-insensitive
- Update README with detailed format flag documentation and examples
- Format flag now works with all syntaxes: --format webp, -f webp, --format=webp
- Default value (webp) is preserved and shown in help text
Co-authored-by: Belphemur <197810+Belphemur@users.noreply.github.com>
Antoine Aflalo