add Ollama support

[neox1de]

Enhancement:

• Added support for Ollama when the Google Gemini API key is not defined in the environment variables.
• Optimized the prompt for faster and more efficient output generation.

[neox1de]

i just updated the installation script, it seems the previous one wasn't working with most distros since they all have different os-releases, so i used their package manager instead of os-release.