Expose generation settings to config / ux

[vegu-ai-tools]

Difficulty here lies in the fact that generation presets aren't per agent as much as they are tailored to agent action (creative, analytical etc.). Some cleanup and abstraction work will need to be done.

Then again, maybe just making the current presets stored in the config is a good start.

Also should reassert the need of some of the presets that currently exist.