Make it possible to pull and delete models for Ollama in Web UI.

Problem/Motivation

Currently you have to sideload the models via the Ollama cli command, it would be nice to add this to the settings page or its own page so you can do it via Drupal, since there is an API for it.

Steps to reproduce

Proposed resolution

Add a page where you can load or remove models for Ollama.

Remaining tasks

User interface changes

API changes

Data model changes