DEV: Add Ollama provider

[nvh0412]

This allows our users to add the Ollama provider and use it to serve our AI bot (completion/dialect).

In this PR, we introduce:

1. DiscourseAi::Completions::Dialects::Ollama which would help us translate by utilizing Completions::Endpoint::Ollama
2. Correct extract_completion_from and partials_from in Endpoints::Ollama

Also

1. Add tests for Endpoints::Ollama
2. Introduce ollama_model fabricator

Demo

AI Bot

API logs

AI configurations

[SamSaffron]

oh this is not linting at the moment, can you have a look, overall looks good to me but keep in mind we are about to merge: #813

[nvh0412]

Thanks @SamSaffron. I’ll wait for that PR to be merged first.

[SamSaffron]

merged now, so we are just waiting on the linting

[SamSaffron]

Thanks, lets try it out.