docs(config): add documentation for navbar dropdown menu

exampleSite/content/docs/guide/configuration.md

@@ -67,6 +67,27 @@ There are different types of menu items:
 
 These menu items can be sorted by setting the `weight` parameter.
 
+### Nested Menus
+
+You can create dropdown menus by defining child menu items. Child menus appear when clicking on the parent menu item.
+
+```yaml {filename="hugo.yaml"}
+menu:
+  main:
+    - identifier: sdk
+      name: SDK
+    - identifier: python
+      name: Python ↗
+      url: https://python.org
+      parent: sdk
+    - identifier: go
+      name: Go
+      url: https://go.dev
+      parent: sdk
+```
+
+Child menu items need to specify the `parent` parameter with the parent's `identifier` value.
+
 ### Logo and Title
 
 To modify the default logo, edit `hugo.yaml` and add the path to your logo file under `static` directory.
@@ -302,6 +323,7 @@ To customize the search tokenize, set the `params.search.flexsearch.tokenize` pa
 
 ```yaml {filename="hugo.yaml"}
 params:
+  search:
     # ...
     flexsearch:
       # full | forward | reverse | strict
@@ -363,6 +385,7 @@ outputs:
 ```
 
 This will generate an `llms.txt` file at your site's root containing:
+
 - Site title and description
 - Hierarchical listing of all sections and pages
 - Page summaries and publication dates