Merge pull request #7303 from AdrianRomanski/docs/use-content-use-case

Document more thoroughly the use case for useContent with current page's headings

Author: AdrianRomanski

packages/docs/src/routes/docs/(qwikcity)/guides/mdx/index.mdx

@@ -195,4 +195,18 @@ export const Tags = component$(() => {
     </ul>
   );
 });
+
+## `useContent()`
+
+The [`useContent()`](/docs/(qwikcity)/api/index.mdx#usecontent) function retrieves the nearest content information for the current route. The returned object includes:
+
+```ts
+headings: ContentHeading[] | undefined;
+menu: ContentMenu | undefined;
+```
+
+The `headings` array includes data about a markdown file's `<h1>` to `<h6>` [html heading elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/Heading_Elements).
+
+Menus are contextual data declared with `menu.md` files. See [menus file definition](/docs/(qwikcity)/advanced/menu/index.mdx) for more information on the file format and location.
+
 ```