Implement system quotes

[lukehinds]

We have various system quotes: https://github.com/stacklok/research/blob/ecb1cc46f5d2e0e8b1c0d0bd55eedacc5ac67551/rag-in-a-box/internal/processor/chat.go#L24-L103

It may make sense to load these from YAML or JSON outside of the code tree, allow others to customize

[jhrozek]

Just a note, I think we might need to tune them per provider as we've seen during our testing with codegate where Ollama and in general lower-B models were more sensitive than others