docs: align llms.txt and llms-full.txt with ralph format framing

Both LLM-facing files still led with the old "while True loop"
messaging while every other docs surface has been rewritten to
center on the ralph format. Update the taglines, intros, and
landing sections to match.

Co-authored-by: Ralphify <noreply@ralphify.co>

Author: 2 people