fix(series): remove library switcher from detail page, add title tooltips to BookCard

Remove the library selector dropdown from the series detail page
since the page is scoped to the library from the browse page.
Replace it with a simple '← All Series' back link in the sticky bar.

Add title attributes to the shared BookCard template so the full
book title and author are visible on hover (useful for truncated
text with line-clamp).

internal/router/frontend.go

@@ -239,26 +239,6 @@ func registerFrontendRoutes(cfg *Config) {
 			}
 		}
 
-		libraries, err := cfg.Queries.GetUserVisibleLibraries(c.Request().Context(), uuidToPGType(userUUID))
-		if err != nil {
-			log.Printf("GetUserVisibleLibraries failed: %v", err)
-			libraries = []database.GetUserVisibleLibrariesRow{}
-			if errorMsg == "" {
-				errorMsg = "Error loading libraries"
-			}
-		}
-
-		libData := make([]templates.LibraryData, len(libraries))
-		for i, lib := range libraries {
-			libUUID, _ := uuid.FromBytes(lib.ID.Bytes[0:16])
-			libData[i] = templates.LibraryData{
-				ID:          libUUID.String(),
-				Name:        lib.Name,
-				Description: getText(lib.Description),
-				TypeName:    lib.TypeName,
-			}
-		}
-
 		var bookInfoList []handlers.BookInfo
 
 		if libraryID != "" && errorMsg == "" {
@@ -289,7 +269,7 @@ func registerFrontendRoutes(cfg *Config) {
 		}
 
 		var buf bytes.Buffer
-		err = templates.SeriesDetail(user, seriesName, bookInfoList, libData, libraryID, errorMsg).Render(c.Request().Context(), &buf)
+		err = templates.SeriesDetail(user, seriesName, bookInfoList, libraryID, errorMsg).Render(c.Request().Context(), &buf)
 		if err != nil {
 			return err
 		}