…auses the layout to change.

Bug (previous behavior):
    1.Press Ctrl+Shift+F to open the search panel.
    2.Enter any text into the search input.
    3.Press PageUp/PageDown.
    4.The layout shifts to the right, hiding the line that indicates the current tab in the activity bar.

Solution:
When search results are displayed, pressing PageUp or PageDown now moves the cursor to the start or end of the search input, respectively. This is achieved by assigning specific functionality to these keys, overriding their default behavior of moving through the page.

Testing:
A smoke test was implemented to assess the fix. The test involves entering text into the search editor, pressing the PageUp and PageDown keys, and checking for any changes in the activity bar's layout.