Chatbot: Compact content density

[kaylachumley]

all/most of the chatbot components will need a compact variant of their current default components so accomodate a compact content density theme of the chatbot experience. This includes changing the spacing/padding/gap variables throughout to clean up the information density

[kaylachumley]

DEMO: https://pf-virtual-assistant.surge.sh/patternfly-ai/chatbot/overview/demo/compact-chatbot/

[kaylachumley]

Header: padding all around 16px
History menu panel: 16px padding right and left