Remove drf-addons dependency.

### Describe the feature you'd like

We need to remove [drf-addons](https://github.com/101Loop/drf-addons) dependency from this project as we're only using it's minor features only.

We will rewrite these 2 methods:
- get_client_ip
- send_message

And we'll remove usage of `JsonResponse`. Use DRF's `Response` or something.

Please write tests. 🙏🏼
### Is your feature request related to a problem?

### Your Environment

- `drf-user` version(s) (`drf-user --version`:
- Operating System(s):
- Python version(s):

### Additional context

Find where drf-addons is imported and used, likely in views or utils. Locate the get_client_ip and send_message methods and the JsonResponse usage. Write replacements using Django REST Framework's Response and standard Python libraries for IP detection and messaging. Ensure tests cover the new implementations and remove the dependency from requirements.

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