Rewrite wiki as fully flat page names, no / grouping The earlier Category/Page-Name structure (mimicking GitHub Wiki's sidebar auto-grouping feature) caused real, reproducible routing bugs: GitHub's wiki page index appears to key on basename alone in at least some lookup paths, so English and Chinese pages sharing a basename (Controller-Setup, Protocol, Prerequisites, ...) collided -- one URL would serve the wrong language's content, and some combinations 404'd outright, confirmed against the raw git blobs (always correct) vs the rendered wiki page (sometimes wrong or missing). Every page name is now a single globally-unique flat string (English: Controller-Setup-Prerequisites; Chinese: Chinese-Controller-Setup-Prerequisites), which cannot collide. The custom _Sidebar.md still presents them grouped by category and language, so navigation looks the same as before despite the flatter underlying names.
Move Chinese/Index.md to root-level Chinese.md Nested pages under a prefix only route correctly when a root-level page with that exact name also exists (Controller-Setup.md and Protocol.md already followed this pattern for their own subtrees; Chinese/ never had one, which was the actual cause of the earlier 404s, not the zh vs Chinese naming itself). Chinese.md now also doubles as a nicer landing URL (/wiki/Chinese) than /wiki/Chinese/Index would have been.