refactor: add efficient get_aces_for_path method for resource pool checks

Add a new repository method get_aces_for_path() that:
- Queries ACEs for a specific path at database level (more efficient)
- Preloads related user, group, and role objects to prevent 500 errors
- Keeps original get_aces() method unchanged to avoid performance impact

This improves both performance and code clarity for resource pool
deletion safety checks.

gns3server/api/routes/controller/pools.py

@@ -149,8 +149,7 @@ async def delete_resource_pool(
 
     # Check if there are any ACE configurations using this resource pool path
     pool_path = f"/pools/{resource_pool_id}"
-    aces = await rbac_repo.get_aces()
-    using_aces = [ace for ace in aces if ace.path == pool_path or ace.path.startswith(pool_path + "/")]
+    using_aces = await rbac_repo.get_aces_for_path(pool_path)
 
     if using_aces:
         # Build detailed error message with ACE information