Error creating item Invalid index name [items_Randy], must be lowercase

[pedro-cf]

Describe the bug
In a previously working environment, when trying to create a STAC item in a collection with id Randy, I get the following error:

{  
  "code": "BadRequestError",  
  "description": "BadRequestError(400, 'invalid_index_name_exception', 'Invalid index name [items_Randy], must be lowercase')"  
}  

This was previously working but now fails with an invalid index name exception.

To Reproduce
I am unable to reproduce this in a fresh environment.

Expected behavior
The STAC item should be successfully created, as it was before. If uppercase names are now restricted, the API should automatically convert them to lowercase or provide a clearer validation error earlier in the process.

Additional context

• SFEOS v3.2.3 deployed on k8s
• Elasticsearch v8.11.0 deployed on k8s