Make ollama hostname configurable

[digitalstudium]

Ollama can be deployed on remote server, so it would be nice to have an option to set Ollama hostname via environment variable

In this file: https://github.com/insulineru/ai-commit/blob/main/index.js#L78
read ollama hostname from environment variable instead of hardcoded localhost

[mauricionr]

#49