Add settings page for the HuggingFace test generation

# Description
All the hard-coded parameters for the test generation via HuggingFace must be parameterizable from the settings page.

# Definition of Done
* [ ] Create the settings page for the HuggingFace test generation.
* [ ] Move all the hard-coded params into the settings.

Start by locating the settings page and the HuggingFace test-generation entry point, then identify every hard-coded generation parameter. Move those parameters into the settings and make them configurable from the page. Done means the settings page exists and no HuggingFace generation parameters remain hard-coded.

Written by the indexing model from the issue text.