feat(ux): implement sprint 11 user experience module

docs/platform/13-backend-requirements.md

@@ -10,6 +10,7 @@
 - Выдача навигации, статических страниц и feature flags.
 - Product Engagement API для рейтинга, отзывов и вопросов.
 - Advanced Search API для keyword/suggestions/filter metadata/sorting.
+- User Experience API (future-ready): wishlist/compare/saved-searches/recently-viewed sync for authenticated users.
 
 ### Контракт статических страниц
 Backend должен поддерживать формат:
@@ -48,6 +49,19 @@ Backend должен поддерживать формат:
 - GET /search/suggestions?q={term} (future-ready)
 - GET /catalog/filters?category={id}&q={term} (future-ready)
 
+## User Experience endpoints (future-ready)
+- GET /me/wishlist
+- POST /me/wishlist
+- DELETE /me/wishlist/{itemId}
+- GET /me/compare
+- POST /me/compare
+- DELETE /me/compare/{itemId}
+- GET /me/saved-searches
+- POST /me/saved-searches
+- DELETE /me/saved-searches/{id}
+- GET /me/recently-viewed
+- POST /me/recently-viewed
+
 ## Catalog bootstrap contract expectations
 - Backend should populate `catalog.availableSorts` and `catalog.enabledFilters`.
 - Backend should not include product list or filter results inside bootstrap.