docs: Improve the table of contents

There number of pages we have makes it better to show all the pages expanded.

Also, integrating the ToC into the menu avoids having the right menu.

Author: pelme

mkdocs.yml

@@ -4,6 +4,8 @@ theme:
   name: material
   features:
     - content.code.copy
+    - toc.integrate
+    - navigation.expand
   palette:
     - media: "(prefers-color-scheme)"
       toggle: