feat: add bulk move recipes endpoint

Add new move_recipes_bulk endpoint to handle moving multiple recipes simultaneously. This improves efficiency when reorganizing recipe collections by allowing batch operations instead of individual moves.

- Add move_recipes_bulk handler method with proper error handling
- Register new POST /api/lm/recipes/move-bulk route
- Implement bulk move logic in persistence service
- Validate required parameters (recipe_ids and target_path)
- Handle common error cases including validation, not found, and server errors

static/js/recipes.js

@@ -220,6 +220,11 @@ class RecipeManager {
                 refreshVirtualScroll();
             });
         }
+
+        const bulkButton = document.querySelector('[data-action="bulk"]');
+        if (bulkButton) {
+            bulkButton.addEventListener('click', () => window.bulkManager?.toggleBulkMode());
+        }
     }
     
     // This method is kept for compatibility but now uses virtual scrolling
@@ -285,4 +290,4 @@ document.addEventListener('DOMContentLoaded', async () => {
 });
 
 // Export for use in other modules
-export { RecipeManager };
+export { RecipeManager };