### Check for existing issues

- [x] I have searched the existing issues and checked that my issue is not a duplicate.

### What happened?

When uses OpenAI Responses API with background=true I get ModuleNotFoundError (litellm_enterprise not found)

### Steps to Reproduce

When using background=true with OpenAI Responses API, it hits this part of the code, the response status is queued or in_progress, which requires in the litellm_enterprise pacakge to be installed. Reference - https://github.com/BerriAI/litellm/blob/bf02a4a47f08ad8007a24c8da2ffa8de1a1d36a2/litellm/proxy/response_api_endpoints/endpoints.py#L218-L220

### Relevant log output

```shell

```

### What part of LiteLLM is this about?

Proxy

### What LiteLLM version are you on ?

v.1.91.1

### Twitter / LinkedIn details

_No response_