Add scroll-to-element on branch toggle

Call scrollToAgent when toggling agent/tool branches to keep the toggled item visible in the top third of the scrollbox. Improves navigation in long chat sessions.

🤖 Generated with Codebuff
Co-Authored-By: Codebuff <noreply@codebuff.com>

Author: brandonkachen

cli/src/hooks/use-message-renderer.tsx

@@ -365,7 +365,9 @@ export const useMessageRenderer = (props: UseMessageRendererProps): ReactNode[]
                         }
                         return next
                       })
+                      scrollToAgent(id)
                     }}
+                    registerAgentRef={registerAgentRef}
                   />
                 </box>
               </box>
@@ -413,7 +415,9 @@ export const useMessageRenderer = (props: UseMessageRendererProps): ReactNode[]
                       }
                       return next
                     })
+                    scrollToAgent(id)
                   }}
+                  registerAgentRef={registerAgentRef}
                 />
               </box>
             )}