openai/gpt-chat-latest → A (10:1)

Side A changes application behavior by altering sibling navigation so each unranked sibling becomes its own navigation group instead of all unranked siblings being lumped together, updates the documentation to match, and adds a regression test verifying the new grouping. Side B only appends a brief project note ('new public thread form needs fewer words') to a notes file without affecting the code or behavior.