Add per-user ignored audiobooks feature

Introduce a per-user "ignored audiobooks" feature to suppress auto-requests. Changes include:

- Database: add Prisma model IgnoredAudiobook and SQL migration to create ignored_audiobooks table with indexes and FK to users.
- Backend: new API routes to list, add, delete, and check ignored audiobooks (/api/user/ignored-audiobooks, /check/:asin, /:id). Add annotateWithIgnoreStatus utility and integrate it into multiple audiobook list endpoints (popular, new-releases, category, search, authors, series).
- Request creator: add ignore-list check (with sibling-ASIN expansion) and a bypassIgnore option for manual requests; return an 'ignored' reason when blocked.
- Frontend: hooks (useIsIgnored, useToggleIgnore, useIgnoredList) and UI updates — AudiobookCard shows an "Ignored" indicator and AudiobookDetailsModal adds an ignore toggle and propagates local state changes.
- Misc: adjust deduplication duration tolerance (to 5% / min 10 minutes), tweak SWR refresh intervals for shelves/syncing, and small logging/info updates.
- Tests: add unit tests for request-creator ignore logic and update existing tests/mocks to account for ignore annotation; extend prisma test helper with ignoredAudiobook mock.

This commit implements the ignore-list end-to-end (DB, server, client, and tests) so users can ignore specific ASINs and have auto-request flows respect that preference.

tests/api/audiobooks-browse.routes.test.ts

@@ -27,6 +27,13 @@ vi.mock('@/lib/utils/audiobook-matcher', () => ({
   enrichAudiobooksWithMatches: enrichMock,
 }));
 
+// Mock ignore status annotation — pass-through that adds isIgnored: false
+vi.mock('@/lib/utils/ignored-audiobooks', () => ({
+  annotateWithIgnoreStatus: vi.fn(async (books: any[]) =>
+    books.map((b: any) => ({ ...b, isIgnored: false }))
+  ),
+}));
+
 vi.mock('@/lib/middleware/auth', () => ({
   getCurrentUser: currentUserMock,
 }));