docs: New shared Agent topic with updates to existing topics and other stuff (#2160)

Co-authored-by: John Austin <jaustin@squareup.com>
Co-authored-by: Kalvin C <kalvinnchau@users.noreply.github.com>

documentation/docs/guides/updating-goose.md

@@ -1,13 +1,15 @@
 ---
 sidebar_position: 2
+title: Updating Goose
+sidebar_label: Updating Goose
 ---
 
-# Updating Goose
-
 import Tabs from '@theme/Tabs';
 import TabItem from '@theme/TabItem';
 import DesktopInstallButtons from '@site/src/components/DesktopInstallButtons';
 
+The Goose CLI and desktop apps are under active and continuous development. To get the newest features and fixes, you should periodically update your Goose client using the following instructions.
+
 <Tabs groupId="interface">
   <TabItem value="cli" label="Goose CLI" default>
     You can update Goose by running: