Inject a homepage-only language switch into the mdBook frontpage wrapper so the English homepage links to the Chinese homepage and the Chinese homepage links back to the English homepage.
Move the English root site to mdBook, keep the Chinese site as a sub-book, and update CI/deploy to publish .mdbook outputs to docs/ and docs/cn/. Also add regression coverage for placeholder skipping, publish-tree assembly, and shared resource setup.
Parse mlsys.bib to generate author-year inline citations linked to
per-page bibliography sections. Missing bib keys degrade gracefully
to plain text placeholders.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add mdBook configuration rooted at zh_chapters, generate and commit SUMMARY.md, rewrite d2l-specific directives through a Python preprocessor, refresh chapter resource symlinks from the build scripts, and ignore local build-only links and helper directories.
