chore: clean unused deps and files for HF Spaces deploy

fix: flowchart PPO→Policy arrow routes right side, fix reload auto-scroll

fix toc and embed sliders

fix url, fix mermaid zoom perfs, fix model perfs hover

add url changer, fix base model perf, add mermaid zoom

update citations and footer

fix toc and footer quotes

update table of content behavior

update embeds

update