refactor: simplify router configuration and handler setup

- Move JWT middleware creation to shared function
- Simplify library route registration
- Add bulk-add-books endpoint to collections
- Clean up duplicate handler setup code
- Improve route organization and maintainability

internal/router/sync.go

@@ -12,8 +12,8 @@ func registerSyncRoutes(cfg *Config) {
 
 	protected := e.Group("/api", jwtMiddleware)
 
-	// Setup ebook handler routes first
-	h := handlers.SetupRoutes(protected, cfg.Queries, cfg.ConnManager)
+	// Create handler for sync-specific routes
+	h := handlers.NewHandler(cfg.Queries, cfg.ConnManager)
 
 	// Book matching and unlinked book resolution routes
 	sync := protected.Group("/sync")