Add project and branch chat controls

docs/USER_GUIDE.md

@@ -15,6 +15,11 @@ tools, approvals, context, and interactive UI state. Model inference shares the
 single loaded runtime so model weights are not duplicated, while independent
 tool work continues concurrently.
 
+The composer status row shows the current project and, for Git repositories,
+the current local branch. An unsaved draft can be moved with the project menu;
+saved chats keep their original project. Use the branch menu to switch local
+branches when that project's chats are idle.
+
 Quitting with active chats asks for confirmation. Confirming stops their model
 and tool work; canceling leaves every chat running.