Use different llm and embedding api class based on OpenAI key

[nerfZael]

Describe the bug
Changing OpenAI key (setting and deleting) does not change change the between normal and proxy llm and embedding APIs for existing evo instances.

To Reproduce
Steps to reproduce the behavior:

1. Start with a logged in user and without an OpenAI key set
2. Give evo a goal to accomplish
3. Go to settings and set an OpenAI key
4. If the goal is not still running start another one in the same chat.
5. Notice that the llm and embedding proxies are still being used.