feat: add assistant window controls

apps/docs/docs/management/assistant.mdx

@@ -22,6 +22,8 @@ While a response is running, a compact activity bar appears at the bottom of the
 avatar shows a thinking indicator. The activity bar can be opened to follow the response. Completed
 responses add an unread count to the user menu until they are opened or dismissed. The expanded
 conversation has a minimize action that returns it to the activity bar without interrupting a response.
+Its desktop-style window controls can also maximize the conversation to the available viewport or close it
+without leaving an activity bar behind. Each control includes an icon, tooltip, and accessible label.
 The transcript follows streamed output while it is already at the bottom, including fast responses. Scrolling
 up releases that follow state until **Scroll to latest** is selected or the user returns to the bottom.