feat(mdbook): Strip out input elements mdbook can't handle

Makefile.am

@@ -74,7 +74,7 @@ fontsdir = $(datadir)/fonts
 dist_fonts_DATA = fonts/Almendra-Bold.otf fonts/Almendra-BoldItalic.otf fonts/Almendra-Italic.otf fonts/Almendra-Regular.otf fonts/AlmendraDisplay-Regular.otf fonts/AlmendraSC-Bold.otf fonts/AlmendraSC-BoldItalic.otf fonts/AlmendraSC-Italic.otf fonts/AlmendraSC-Regular.otf fonts/FeFlow2.otf fonts/NexaRustExtras-Free.otf fonts/NexaRustHandmade-Extended-Free.otf fonts/NexaRustSans-Black-Free.otf fonts/NexaRustScriptL-0-Free.otf fonts/NexaRustSlab-BlackShadow01-Free.otf fonts/Nymphette.ttf fonts/PrintersOrnamentsOne.ttf
 
 filtersdir = $(datadir)/pandoc-filters
-dist_filters_DATA = pandoc-filters/chapterid.lua pandoc-filters/epubclean.lua pandoc-filters/svg2pdf.py pandoc-filters/withoutfootnotes.lua pandoc-filters/withoutheadinglinks.lua pandoc-filters/withoutlinks.lua pandoc-filters/withverses.lua
+dist_filters_DATA = pandoc-filters/chapterid.lua pandoc-filters/epubclean.lua pandoc-filters/strip_for_mdbook.lua pandoc-filters/svg2pdf.py pandoc-filters/withoutfootnotes.lua pandoc-filters/withoutheadinglinks.lua pandoc-filters/withoutlinks.lua pandoc-filters/withverses.lua
 
 packagesdir = $(datadir)/packages
 dist_packages_DATA = packages/crop.lua packages/markdown.lua packages/verseindex.lua

pandoc-filters/strip_for_mdbook.lua

@@ -0,0 +1,22 @@
+-- c.f. pandoc-filters/withoutheadinglinks.lua
+Header = function (element)
+  return pandoc.walk_block(element, {
+      -- c.f. pandoc-filters/epubclean.lua
+      Note = function (_)
+        return {}
+      end,
+      Link = function (element)
+        return element.content
+      end
+    })
+end
+
+function remove_attr (element)
+  if element.attr then
+    element.attr = pandoc.Attr()
+    return element
+  end
+end
+
+Inline = remove_attr
+Block = remove_attr

scripts/split_mdbook_src.zsh.in

@@ -15,8 +15,12 @@ function trunc() {
 
 trunc $dir/$of
 
-@PANDOC@ $src --markdown-headings=atx --wrap=none --to=commonmark_x-smart+gfm_auto_identifiers --reference-location=section |
-@PERL@ -pne 's/{osis=".*"}//g' |
+@PANDOC@ $src \
+  --markdown-headings=atx \
+  --wrap=none \
+  --reference-location=section \
+  --to=commonmark_x-smart \
+  --lua-filter=$CASILEDIR/pandoc-filters/strip_for_mdbook.lua |
 while read line; do
   unset title slug
   # Check for chapter header