fix: remove extra comments & add description for handleKeyDown

Author: filippovskii09

src/courseware/course/sidebar/common/hooks/useSidebarFocusAndKeyboard.js

@@ -45,6 +45,13 @@ export const useSidebarFocusAndKeyboard = (sidebarId, triggerButtonSelector = '.
     focusSidebarTriggerBtn();
   }, [toggleSidebar, focusSidebarTriggerBtn]);
 
+  /**
+   * Handles Tab key navigation when focus is on the standard sidebar close button.
+   * Implements the logic for moving focus out of the sidebar to specific elements
+   * on the main page in a predefined sequence, or back to the trigger button on Shift+Tab.
+   *
+   * @param {KeyboardEvent} event - The keyboard event object.
+   */
   const handleKeyDown = useCallback((event) => {
     if (event.key !== 'Tab') {
       return;

src/courseware/course/sidebar/common/hooks/useSidebarFocusAndKeyboard.test.jsx

@@ -1,4 +1,3 @@
-// hooks/useSidebarFocusAndKeyboard.test.js (або .jsx)
 import { renderHook, act } from '@testing-library/react';
 import SidebarContext from '../../SidebarContext';
 import { useSidebarFocusAndKeyboard } from './useSidebarFocusAndKeyboard';
@@ -165,7 +164,6 @@ describe('useSidebarFocusAndKeyboard', () => {
       });
 
       expect(mockEvent.preventDefault).toHaveBeenCalledTimes(1);
-      // Перевіряємо фокус тригера
       act(() => { jest.runAllTimers(); });
       expect(triggerButtonMock.focus).toHaveBeenCalledTimes(1);
       expect(tryFocusAndPreventDefault).not.toHaveBeenCalled();