Test multiple AI LLMs

Problem/Motivation

We have been mostly testing against Gemini. We should test the module against other LLMs like ones from OpenAI and Anthropic.

Steps to reproduce

Test either the dev version or alpha version with other LLMs, configure those LLMs for 'Chat' and 'Chat with Structured Response'

Remaining tasks

OpenAI

1. Install and enable the module
2. Install and enable the OpenAI https://www.drupal.org/project/openai → module and configure it
3. Test the migration process (docs to be provided)

Anthropic

1. Install and enable the module
2. Install and enable the Anthropic https://www.drupal.org/project/ai_provider_anthropic → module and configure it
3. Test the migration process (docs to be provided)