Cell toolbar disappears when viewport shrinks

[Yahiewi]

This is actually a Jupyter issue, but it could be worth fixing for this extension:

Screencast.from.2026-07-01.13-23-44.mp4

As you can see if the content of the first line of the cell is long enough and the viewport is small enough, the toolbar (with our question mark button) disappears. I feel this may confuse users who may have both the file browser open on the left and the chat open on the right, which would be quite common.