Add interactive ebook search & selection

Introduce interactive ebook support: adds two API endpoints to search (interactive-search-ebook) and create/select ebook requests (select-ebook), plus server-side handlers to route Anna's Archive (direct) and indexer (torrent/NZB) downloads. Frontend: extend RequestActionsDropdown and InteractiveTorrentSearchModal to support an "ebook" search mode and selection flow, and add hooks (useInteractiveSearchEbook / useSelectEbook). Settings: add ebook_auto_grab_enabled with UI toggle and enforce disabling when no ebook sources are enabled; settings GET/PUT updated to persist the flag (default = true to preserve behavior). Documentation updated (scheduler, ebook-sidecar, settings pages) and ranking algorithm docs/tests extended to cover ebook-related normalization and matching cases. Includes logging and ranking integration for indexer results and normalization for Anna's Archive handling.

src/app/admin/settings/tabs/EbookTab/useEbookSettings.ts

@@ -82,6 +82,7 @@ export function useEbookSettings({ ebook, onChange, onSuccess, onError, markAsSa
           format: ebook.preferredFormat || 'epub',
           baseUrl: ebook.baseUrl || 'https://annas-archive.li',
           flaresolverrUrl: ebook.flaresolverrUrl || '',
+          autoGrabEnabled: ebook.autoGrabEnabled ?? true,
         }),
       });