Creates a second version of the doxygen html output suitable for embedding in our jekyll-based web site. This version turns off the doxygen treeview, but then borrows the javascript menu files from the treeview version. We then edit the html to remove the headers, and edit the menu files for inlining into our web site's single array.
Furthermore, we generate keyword search term data so that searches using lunr for functions or types result in direct links to their anchors within their pages. It generates keyword tokens for each component of an underscore-separated multi-word type, along with tokens for each prefix (e.g., so that "dr_mutex" will find "dr_mutex_*").
Adds installation into a "docs_embed" directory.
Adds deployment logic to package.cmake to copy the embedded html to a top level "html_embed", along with new steps in the ci-package GA workflow to take the embedded html files and push them to the dynamorio.github.io repository.
Issue: #4111