Add a maximize/full-screen toggle for the problem statement

[tanmaythegreat]

I have a small feature request that I think would improve the problem-solving experience.
The problem statement is displayed inside the plugin window along with the toolbar and other controls. While this works well, the available reading area is somewhat limited, especially for longer problems, also at times somewhat distracting.

Proposed Improvement

It would be great to have a maximize/full-screen toggle (for example, in the top-right corner of the problem view) that expands the problem statement to occupy the entire available window. (not the full screen but only the plugin window)
This would allow users to:
Focus on reading the problem without distractions.
View more of the statement at once, reducing the need for scrolling.
Better utilize larger monitors and IDE windows.

The toggle could simply switch between the current layout and a maximized reading mode, while allowing users to return to the normal layout with a single click

[dj258255]

Thanks for the suggestion, this was a nice one to add.

I went with a hover toggle in the top-right corner of the problem view (like you suggested). It stays hidden while you read and only fades in when your mouse is over the statement, so it never gets in the way. One click maximizes the statement to fill the whole plugin window — the toolbar, tab strip, and timer controls all hide, and clicking again brings everything back.

I kept the thin timer progress bar visible even in maximized mode, so you can still keep an eye on the time while focusing on the problem.

PR: #40