Icons of Chat-Input are on top of plan-sidebar

When resizing the window to a smaller screen size (but still reasonable) the icons of the chat-input (for prompting the AI) are moved on top of the new plan sidebar (introduced in #596 )

<img width="622" height="185" alt="Image" src="https://github.com/user-attachments/assets/bdc6a18c-d342-4876-9923-7338913d2dfd" />