docs: collapse tool sidebar sections with navigation.indexes and prune

Remove navigation.sections (expanded all sub-items for every tool at once)
Replace with navigation.indexes + navigation.prune so each tool section
only expands when active, keeping the sidebar clean.

Author: Kristopher Turner

mkdocs.yml

@@ -21,7 +21,8 @@ theme:
         name: Switch to light mode
   features:
     - navigation.tabs
-    - navigation.sections
+    - navigation.indexes
+    - navigation.prune
     - navigation.top
     - navigation.footer
     - content.code.copy