help: Move "Configure how links open" to the Apps section.

- Moves page to the "Apps" section of the sidebar.
- Adds "in mobile apps" to the top-of-page title.

Follow-up to #24447.

help/configure-how-links-open.md

@@ -1,4 +1,4 @@
-# Configure how links open
+# Configure how links open in mobile apps
 
 You can configure whether website links will open directly in the Zulip app, or
 in your device's default browser.

help/include/sidebar_index.md

@@ -86,7 +86,6 @@
 * [View your mentions](/help/view-your-mentions)
 * [Star a message](/help/star-a-message)
 * [View and browse images](/help/view-and-browse-images)
-* [Configure how links open](/help/configure-how-links-open)
 * [View messages sent by a user](/help/view-messages-sent-by-a-user)
 * [Link to a message or conversation](/help/link-to-a-message-or-conversation)
 * [Searching for messages](/help/search-for-messages)
@@ -133,6 +132,7 @@
 * [Download apps for every platform](https://zulip.com/apps/)
 * [Desktop installation guides](/help/desktop-app-install-guide)
 * [Supported browsers](/help/supported-browsers)
+* [Configure how links open](/help/configure-how-links-open)
 * [Connect through a proxy](/help/connect-through-a-proxy)
 * [Use a custom certificate](/help/custom-certificates)