Improved documentation generation, no more hacky sed/awk!

docs/pandoc/lua/code-default-to-nix.lua

@@ -0,0 +1,9 @@
+-- This function is called for each CodeBlock element in the document.
+function CodeBlock(block)
+  -- Check if the code block does not have a language specified.
+  if block.classes[1] == nil then
+    -- Set the language of the code block to "nix".
+    block.classes[1] = "nix"
+  end
+  return block
+end