Add missing utoipa annotations:
- GET /books/{id}/thumbnail
- GET/POST /settings, /settings/{key}
- POST /settings/cache/clear
- GET /settings/cache/stats, /settings/thumbnail/stats
Add 'settings' tag and register all new schemas.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- Change all instances of AppState to reference the new state module across multiple files for consistency.
- Clean up imports in auth, books, index_jobs, libraries, pages, search, settings, thumbnails, and tokens modules.
- Simplify main.rs by removing unused code and organizing middleware and route handlers under the new handlers module.
- Add magic bytes validation for extracted CBR images
- Add hex dump for debugging invalid images
- Show first entries when listing CBR archive
- Remove unused structs and functions from settings.rs
- Add -y flag to unrar for auto-confirm
