fix(ui): show read action on JS-rendered dashboard cards

The dashboard re-renders its sections client-side (library switch,
refresh, saving settings) via renderBookCard in dashboard.ts, which was
still the old markup with no .book-card-action overlay. So the read
button appeared on the server-rendered cards but vanished as soon as the
dashboard re-rendered, while the bookshelf (always templ-rendered) kept
working.

- Rewrite renderBookCard to match the templ BookCard: detail link plus
  the play/read action overlay, routing to the reader or the detail page
  when the book has an active conflict.
- Add has_conflict to the BookInfo TS type and stamp it in the dashboard
  sections API (GetSections) so client-rendered cards can route correctly.
- Add pointer-events-none / group-hover:pointer-events-auto to the
  client-rendered carousel nav buttons so they no longer swallow hover
  over edge cards, matching the templ fix.

web/src/types/api.d.ts

@@ -94,13 +94,14 @@ interface CollectionData {
 }
 
 // Matches handlers.BookInfo JSON response (internal/handlers/collections.go:66-71)
-// JSON tags: media_item_id, title, author, cover_image_path
-// Used in: collections.templ (server-rendered), collections.ts
+// JSON tags: media_item_id, title, author, cover_image_path, has_conflict
+// Used in: collections.templ (server-rendered), collections.ts, dashboard.ts
 interface BookInfo {
   media_item_id: string;
   title: string;
   author: string;
   cover_image_path: string;
+  has_conflict: boolean;
 }
 
 // Dashboard type definitions